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现在进行式 現在進行式 English Grammar CHAPTER 3. THE PRESENT CONTINUOUS 1. Uses of the present continuous In English, the Present Continuous tense is usually used to express continuing, ongoing actions which are taking place at the moment of speaking or writing. In the examples given below, the verbs in the Present Continuous tense are underlined. e.g. Right now I am cooking supper. At the moment the plane is flying over the Gulf of St. Lawrence. The Present Continuous tense is often used in conversation. e.g. "What are you doing?" "I am working on my English assignment." Occasionally, the Present Continuous tense is used to refer to a future event. e.g. We are leaving tomorrow. 2. Formation of the present continuous The Present Continuous tense of any verb is formed from the Simple Present of the auxiliary to be, followed by what is generally referred to as the present participle of the verb. The present participle of a verb is formed by adding ing to the bare infinitive. For instance, the present participle of the verb to work is working. Thus, the Present Continuous tense of the verb to work is conjugated as follows: I am working you are working he is working she is working it is working we are working they are working See Exercise 1. 3. Spelling rules for the formation of the present participle Some verbs change their spelling when the ending ing is added to form the present participle. a. Verbs ending in a silent e When a verb ends in a silent e, the silent e is dropped before the ending ing is added. For example: Infinitive Present Participle to close closing to dine dining to leave leaving to move moving However, when a verb ends in an e which is not silent, the final e is not dropped before the ending ing is added. For example: Infinitive Present Participle to be being to see seeing b. Verbs ending in ie When a verb ends in ie, the ie is changed to y before the ending ing is added. For example: Infinitive Present Participle to die dying to lie lying When a verb ends in y, no change is made before the ending is added. For example: Infinitive Present Participle to fly flying to play playing See Exercise 2. c. One-syllable verbs ending in a single consonant preceded by a single vowel Except in the case of the final consonants w, x and y, when a one-syllable verb ends in a single consonant preceded by a single vowel, the final consonant must be doubled before the ending ing is added. The reason for this is to reflect the fact that the pronunciation of the single vowel does not change when the ending ing is added. English vowels have a variety of pronunciations. For instance, each English vowel has two contrasting pronunciations, which are sometimes referred to as short and long. Vowels which are followed by two consonants, and vowels which are followed by a single consonant at the end of a word, are generally pronounced short. In contrast, vowels which are followed by a single consonant followed by another vowel are generally pronounced long. In the table below, the underlined vowels in the left-hand column are pronounced short; whereas the underlined vowels in the right-hand column are pronounced long. For example: Short Vowels Long Vowels fat fate tapping taping let delete win wine filling filing not note hopping hoping flutter flute Thus, in the case of most one-syllable verbs ending in a single consonant preceded by a single vowel, the vowel is pronounced short. In order to reflect the fact that the vowel is also pronounced short in the corresponding present participle, except in the case of w, x and y, the final consonant must be doubled before the ending ing is added. In the following examples, the consonants which have been doubled are underlined. For example: Infinitive Present Participle to nod nodding to dig digging to run running to clap clapping to set setting When a verb ends in w, x or y preceded by a single vowel, the final consonant is not doubled before the ending is added. For example: Infinitive Present Participle to draw drawing to fix fixing to say saying It should also be noted that when a verb ends in a single consonant preceded by two vowels, the final consonant is not doubled before the ending is added. The reason for this is that two vowels together are generally pronounced long. For example: Infinitive Present Participle to rain raining to read reading to meet meeting to soak soaking See Exercise 3. d. Verbs of more than one syllable which end in a single consonant preceded by a single vowel When a verb of more than one syllable ends in a single consonant other than w, x or y preceded by a single vowel, the final consonant is doubled to form the present participle only when the last syllable of the verb is pronounced with the heaviest stress. For instance, in the following examples, the last syllables of the verbs have the heaviest stress, and the final consonants are doubled to form the present participles. In these examples, the syllables pronounced with the heaviest stress are underlined. For example: Infinitive Present Participle to expel expelling to begin beginning to occur occurring to omit omitting When a verb of more than one syllable ends in w, x or y, the final consonant is not doubled before the ending ing is added. In the following examples, the syllables pronounced with the heaviest stress are underlined. For example: Infinitive Present Participle to allow allowing to affix affixing to convey conveying When the last syllable of a verb is not pronounced with the heaviest stress, the final consonant is usually not doubled to form the present participle. For instance, in the following examples, the last syllables of the verbs do not have the heaviest stress, and the final consonants are not doubled to form the present participles. In these examples, the syllables pronounced with the heaviest stress are underlined. For example: Infinitive Present Participle to listen listening to order ordering to focus focusing to limit limiting If necessary, a dictionary can be consulted to determine which syllable of a verb has the heaviest stress. Many dictionaries use symbols such as apostrophes to indicate which syllables are pronounced with the heaviest stress. See Exercise 4. It should be noted that British and American spelling rules differ for verbs which end in a single l preceded by a single vowel. In British spelling, the l is always doubled before the endings ing and ed are added. However, in American spelling, verbs ending with a single l follow the same rule as other verbs; the l is doubled only when the last syllable has the heaviest stress. In the following examples, the syllables with the heaviest stress are underlined. For example: Infinitive Present Participle American Spelling British Spelling to signal signaling signalling to travel traveling travelling to compel compelling compelling to propel propelling propelling From these examples it can be seen that the American and British spellings for verbs ending in a single l differ only when the last syllable does not have the heaviest stress. 4. Questions and negative statements a. Questions In the Present Continuous, the verb to be acts as an auxiliary. As is the case with other English tenses, it is the auxiliary which is used to form questions and negative statements. To form a question in the Present Continuous tense, the auxiliary is placed before the subject. For example: Affirmative Statement Question I am working. Am I working? You are working. Are you working? He is working. Is he working? She is working. Is she working? It is working. Is it working? We are working. Are we working? They are working. Are they working? See Exercise 5. b. Negative statements To form a negative statement, the word not is added after the auxiliary. For example: Affirmative Statement Negative Statement I am working. I am not working. You are working. You are not working. He is working. He is not working. She is working. She is not working. It is working. It is not working. We are working. We are not working. They are working. They are not working. See Exercise 6. c. Negative questions To form a negative question, the auxiliary is placed before the subject, and the word not is placed after the subject. However, when contractions are used, the contracted form of not follows immediately after the auxiliary. Although there is no universally accepted contraction for am not, the expression aren't I? is often used in spoken English. For example: Without Contractions With Contractions Am I not working? [Aren't I working?] - used in speaking Are you not working? Aren't you working? Is he not working? Isn't he working? Is she not working? Isn't she working? Is it not working? Isn't it working? Are we not working? Aren't we working? Are they not working? Aren't they working? See Exercise 7. d. Tag questions Tag questions are also formed using the auxiliary. In the following examples, the tag questions are underlined. In spoken English, aren't I? is often used as a tag question. For example: Affirmative Statement Affirmative Statement with Tag Question I am working. I am working, am I not? You are working. You are working, aren't you? He is working. He is working, isn't he? She is working. She is working, isn't she? It is working. It is working, isn't it? We are working. We are working, aren't we? They are working. They are working, aren't they? See Exercise 8. 5. Comparison of the uses of the simple present and present continuous As pointed out in Chapter 1, the Simple Present tense may be used for stating general truths, and for referring to actions which occur at regular intervals. In the following examples, the verbs in the Simple Present tense are underlined. e.g. Nova Scotia is a Canadian province. Geese fly south every winter. In contrast, the Present Continuous tense is usually used to refer to ongoing actions happening at the time of speaking or writing. In the following examples, the verbs in the Present Continuous tense are underlined. e.g. Right now, I am visiting the province of Nova Scotia. At the moment, a flock of geese is flying overhead. See Exercise 9. English Grammar EXERCISES for CHAPTER 3. THE PRESENT CONTINUOUS 1. Using the Present Continuous tense, fill in the blanks with the correct forms of the verbs shown in brackets. For example: He _________ hard. (to work) He is working hard. We ____________ anxious. (to feel) We are feeling anxious. 1. I _______________ the questions. (to answer) 2. You ________________ boots. (to wear) 3. We ______________ for work. (to look) 4. She ______________ her friend. (to call) 5. He _______________ a house. (to build) 6. They _______________ supper. (to cook) 7. We ______________ a story. (to tell) 8. You ______________ for the bus. (to wait) 9. I _______________ a book. (to read) 10. They _______________ berries. (to pick) Answers 2. Using the Present Continuous tense, fill in the blanks with the correct forms of the verbs shown in brackets. For example: They _____________ the lemons. (to squeeze) They are squeezing the lemons. It ________ on the sidewalk. (to lie) It is lying on the sidewalk. I ___________ the groceries. (to carry) I am carrying the groceries. 1. She ________________ a letter. (to write) 2. They _________________ about it. (to worry) 3. He _________________ jam. (to make) 4. It _________________. (to die) 5. We _______________ to school. (to hurry) 6. She _________________ us to do it. (to dare) 7. You ________________ on the blanket. (to lie) 8. He _________________ the problem. (to solve) 9. I _________________ now. (to leave) 10. They _________________ to help us. (to try) Answers 3. Using the Present Continuous tense, fill in the blanks with the correct forms of the verbs shown in brackets. For example: We ___________ to come. (to plan) We are planning to come. They _________ the lawn. (to mow) They are mowing the lawn. It __________. (to rain) It is raining. 1. I _______________ the grass. (to cut) 2. It _______________ downstream. (to float) 3. They _________________ the game. (to win) 4. We _________________ the present. (to wrap) 5. She _________________ lettuce. (to grow) 6. He _________________ for us. (to look) 7. I _________________ a sweater. (to knit) 8. They _________________ wood. (to saw) 9. She _________________ the windows. (to clean) 10. We _________________ the floor. (to scrub) 11. I ________________ the toaster. (to fix) 12. He _________________ his coffee. (to sip) 13. They __________________ the hedge. (to trim) 14. You _________________ the ducks. (to feed) 15. She _________________ her head. (to nod) Answers 4. Each of the following sentences is preceded by a bare infinitive, the most heavily stressed syllable of which is underlined. Paying attention to whether or not the final consonant should be doubled before ing is added, fill in the blanks with the present participles corresponding to the bare infinitives. Use the American spelling for verbs ending in l. For example: whisper: They are __________ to their friends. They are whispering to their friends. refer: I was _________ to your letter. I was referring to your letter. 1. open: I am _____________ the door. 2. display: She is ______________ her talents. 3. submit: He is _______________ his report tomorrow. 4. limit: The store is _____________ the number of items on sale. 5. permit: We are not _____________ him to go. 6. sharpen: They are _______________ the pencils. 7. confer: She is ________________ with her colleagues. 8. focus: He is ________________ the camera. 9. repel: They are ________________ the attack. 10. shovel: I am ________________ the steps. 11. destroy: Hail is _______________ the crops. 12. dispel: They are _______________ our doubts. 13. squander: He is _______________ his money. 14. prefer: We are _______________ our new school to the old one. 15. color: The child is ______________ the picture. 16. unravel: We are _____________ the wool. 17. propel: Jet engines are _______________ the plane. 18. flower: The pansies are _______________ 19. infer: They are ______________ that we do not want to come. 20. listen: The children are ______________ to us. Answers 5. Change the following affirmative statements into questions. For example: It is snowing. Is it snowing? They are being cautious. Are they being cautious? 1. I am learning English. 2. You are carrying a parcel. 3. It is growing colder. 4. We are living in Halifax. 5. They are running a race. 6. He is drinking coffee. 7. She is shopping for presents. 8. I am cleaning the window. 9. We are buying pencils. 10. They are playing football. Answers 6. Change the affirmative statements given in Exercise 5 into negative statements. For example: It is snowing. It is not snowing. They are being cautious. They are not being cautious. Answers 7. Change the affirmative statements given in Exercise 5 into negative questions. Except when the subject of the verb is I, write both the form without contractions and the form with contractions. For example: It is snowing. Is it not snowing? Isn't it snowing? They are being cautious. Are they not being cautious? Aren't they being cautious? Answers 8. Add negative tag questions to the affirmative statements given in Exercise 5. Except when the subject of the verb is I, use contractions for the tag questions. For example: It is snowing. It is snowing, isn't it? They are being cautious. They are being cautious, aren't they? Answers 9. For each of the following sentences, determine whether the Simple Present tense or the Present Continuous tense is more appropriate, and fill in the blank with the correct form of the verb given in brackets. For example: Right now, he ________ ridiculous. (to be) Right now, he is being ridiculous. She ______ to Sydney every weekend. (to drive) She drives to Sydney every weekend. 1. At the moment, I __________________ supper. (to cook) 2. He ________________ the paper every weekday. (to read) 3. We ________________ right now. (to study) 4. She ________________ every day. (to study) 5. Now it _______________. (to rain) 6. They ______________ to Mexico every year. (to travel) 7. Just now we ________________ the shopping. (to do) 8. She always ________________ correctly.( to answer) 9. You ________________ never late. (to be) 10. Now I ________________ to the radio. (to listen) 11. Each Sunday, we ________________ the flea market. (to visit) 12. At present, I ________________ for work. (to look) Answers ANSWERS for CHAPTER 3. THE PRESENT CONTINUOUS Answers to Exercise 1: 1. am answering 2. are wearing 3. are looking 4. is calling 5. is building 6. are cooking 7. are telling 8. are waiting 9. am reading 10. are picking Answers to Exercise 2: 1. is writing 2. are worrying 3. is making 4. is dying 5. are hurrying 6. is daring 7. are lying 8. is solving 9. am leaving 10. are trying Answers to Exercise 3: 1. am cutting 2. is floating 3. are winning 4. are wrapping 5. is growing 6. is looking 7. am knitting 8. are sawing 9. is cleaning 10. are scrubbing 11. am fixing 12. is sipping 13. are trimming 14. are feeding 15. is nodding Answers to Exercise 4: 1. opening 2. displaying 3. submitting 4. limiting 5. permitting 6. sharpening 7. conferring 8. focusing 9. repelling 10. shoveling 11. destroying 12. dispelling 13. squandering 14. preferring 15. coloring 16. unraveling 17. propelling 18. flowering 19. inferring 20. listening Answers to Exercise 5: 1. Am I learning English? 2. Are you carrying a parcel? 3. Is it growing colder? 4. Are we living in Halifax? 5. Are they running a race? 6. Is he drinking coffee? 7. Is she shopping for presents? 8. Am I cleaning the window? 9. Are we buying pencils? 10. Are they playing football? Answers to Exercise 6: 1. I am not learning English. 2. You are not carrying a parcel. 3. It is not growing colder. 4. We are not living in Halifax. 5. They are not running a race. 6. He is not drinking coffee. 7. She is not shopping for presents. 8. I am not cleaning the window. 9. We are not buying pencils. 10. They are not playing football. Answers to Exercise 7: 1. Am I not learning English? 2. Are you not carrying a parcel? Aren't you carrying a parcel? 3. Is it not growing colder? Isn't it growing colder? 4. Are we not living in Halifax? Aren't we living in Halifax? 5. Are they not running a race? Aren't they running a race? 6. Is he not drinking coffee? Isn't he drinking coffee? 7. Is she not shopping for presents? Isn't she shopping for presents? 8. Am I not cleaning the window? 9. Are we not buying pencils? Aren't we buying pencils? 10. Are they not playing football? Aren't they playing football? Answers to Exercise 8: 1. I am learning English, am I not? 2. You are carrying a parcel, aren't you? 3. It is growing colder, isn't it? 4. We are living in Halifax, aren't we? 5. They are running a race, aren't they? 6. He is drinking coffee, isn't he? 7. She is shopping for presents, isn't she? 8. I am cleaning the window, am I not? 9. We are buying pencils, aren't we? 10. They are playing football, aren't they? Answers to Exercise 9: 1. am cooking 2. reads 3. are studying 4. studies 5. is raining 6. travel 7. are doing 8. answers 9. are 10. am listening 11. visit 12. am looking