• 6-4 The present perfect



    1 Summary

    The present perfect is an important verb tense in English. It is used to talk about things that happened at unspecified times in the past. The present perfect makes a connection between the past and the present.


    2 Form

    To form the present perfect, you need to know how to form the past participle of verbs. With regular verbs, the past participle form is the same as the simple past form--they both end in "-ed." But some verbs are irregular. Note that this is not a complete list of irregular verbs.


    3 Expression

    The form of the present perfect is "have" or "has" + past participle. With the pronouns "I," "you," "we," and "they," "have" is usually shortened to "'ve" in spoken English. With the pronouns "she," "he," and "it," "has" is usually shortened to "'s" in spoken English.

    have/has + seen(been, done, eaten)

    My friends have seen that moive.

    He's been to Paris.

    Mary has done the job.


    4 How to use

    The present perfect is used for three main purposes.

    First, it can show that something happened at an unspecified time in the past. The sentence on the screen tells us that Michael finished his report some time in the past, but we don't know exactly when he finished it. "Already" can be used to emphasize that something happened before now.

    Michael has finished his report.

    Thomas has left already.

    I've already paid for our drinks.


    Second, the present perfect can also show that something was repeated at two or more unspecified times in the past. The sentence on the screen tells us that Bob saw a play five times in the past but doesn't tell us when he saw it.

    Bob has seen that play five times.

    I have been to that restaurant a million times.

    Yoshiko has visited France many times.


    Finally, the present perfect can be used with "since" or "for" to show that something began in the past and continues into the present. "Since" is followed by the specific time that an action began. "For" is followed by the length of time of an action.

    Karl has worked here since January.

    Karl has worked here for four months.

    I have been here since 7:00 a.m.

    I have been here for three hours.


    5 Question forms

    Use the present perfect to ask if something happened at an unspecified time in the past. The form is "have/has" + subject + past participle. "Ever" after the subject emphasizes that you are asking if something happened at any time at all. "Yet" at the end of the sentence emphasizes that something is expected to happen.

    Have you learned to play the piano?

    Has she talked to her manager yet?

    Has Karl ever visited France?


    6 Negative forms

    The negative form ("have/has" + "not" + past participle) shows that something didn't happen before now. "Have not" and "has not" are often shortened to "haven't" and "hasn't." "Never" after "have/has" emphasizes that something has not happened. "Yet" at the end of the sentence emphasizes that something might still happen.

    have/has + not + (gone, paid, heard, eaten)

    We haven't gone to that show.

    Joe has not paid for his ticket yet.

    Anna has never heard that story.

    I have never eaten here.

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  • 原文地址:https://www.cnblogs.com/Latiny/p/8555210.html
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