VOA慢速英语2015 英语日常语法:一般过去时和现在完成时

Everyday Grammar - Simple Past and Present Perfect 英语日常语法:一般过去时和现在完成时

In this week’s episode¹ of Everyday Grammar we’re going to help you understand the difference between the simple past and the present perfect. English learners often confuse these two verb tenses.

Let’s start with an example. Can you tell the difference between these two sentences?

Sentence one: I saw the movie.

Sentence two: I have seen the movie.

Sentence one uses the simple past tense. Sentence two uses the present perfect tense.

“I saw the movie” and “I have seen the movie” both refer to an action that was finished in the past. But there is one important difference: “I saw the movie” suggests that you saw the movie at a specific time in the past. “I have seen the movie” suggests that you saw the movie at an unknown time in the past. 

Use the simple past to talk about a finished action that happened at a specific time. For example, “I went out with my friends last night.” The adverb “last night” is not required, but it does help clarify that the event happened at a specific time.

That’s the easy part. Now let’s talk about the present perfect. You form the present perfect by using “have” or “has” followed by the past participle form of the verb.  For example, “I have graduated from college.” The present perfect confuses English learners because it refers to a past action. It is also called “present perfect” because speakers use it to stress the importance of a past event in the present. The sentence “I have graduated from college,” emphasizes the present effect of a past event -- graduation. The exact time of the graduation is not important.

There are four more common situations that require the present perfect.

First, it can express a repeated action.  When an action happened more than one time in the past, use the present perfect. For example, “I have seen the movie three times”.

Second, it is common to use the present perfect with the words “for” and “since.” “For” and “since” are adverbs that tell about the duration of an activity. They answer the question “how long?” For example, “I have studied English for a long time”.

Third, the negative adverb “never” requires the present perfect. You can say, “I have never been to France.” You would not say, “I did never go to France.”

Finally, when asking a question in the present perfect, use “ever,” as in, “Have you ever won the lottery²?” Listen for the present perfect question in this song by the American rock band Creedence Clearwater Revival³.

“I wanna know have you ever seen the rain?

I wanna know have you ever seen the rain

Coming down on a sunny day?”

In an informal situation, you can take out the word “have” in a present perfect question. Listen to actor Jack⁴ Nicholson playing the Joker in the 1989 movie Batman. Before the Joker takes his victims, he asks them an unusual question.

“Tell me something, my friend. You ever danced with the devil in the pale moonlight?”

Here’s a tip: pay close attention to adverbs. Adverbs give hints, or clues, about which verb tense you should use. Take a look at the reference⁵ list below.

A good way to practice the present perfect is to ask an English-speaking friend if he or she has ever done something. “Have you ever flown in an airplane?” or “Have you ever seen the Grand Canyon⁶?” You could even ask something more profound⁷ like, “Have you ever seen the rain coming down on a sunny day?”

"I wanna know have you ever seen the rain

Coming down on a sunny day?”

Reference

Forming the present perfect

Have/has + past participle verb

Ex. I have proven her theory.

Ex. She has gotten promoted.

Common adverbs in the simple past: last night, last year, yesterday, today, ago, first, then, later, when

Ex. Yesterday morning, I went to the store.

Ex. When I lived in Boston, I worked at a deli.

Common adverbs in the present perfect: before, after, already, yet, for, since, recently, still, time

Ex. I have already eaten.

Ex. I have already visited Angola three times.

Tip 1: Be careful of irregular verbs in the present perfect. With irregular verbs, the simple past and the past participle form are usually different.

INCORRECT: I have already did it.

CORRECT: I have already done it.

Tip 2: Make sure to use “has” for the third person in the present perfect.

INCORRECT: She have not read the book yet.

CORRECT: She has not read the book yet.

Words in This Story

simple past tense – n. the basic form of the past tense in English. It is used to describe events that finished at a specific time in the past.

present perfect tense – n. A grammatical⁸ combination of the present tense and the perfect aspect, used to express a past event that has present consequences.

unspecified – adj. not specified⁹ or particular

clarify – v. to make (something) clear or clearer: such as

duration –n. the length of time that something exists or lasts

victim – n. a person who has been attacked, injured, robbed, or killed by someone else

pale – adj. light in color

profound – adj. having or showing great knowledge or understanding

1 episode   

n.（作品的一段）情节，插曲，系列事件中之一

参考例句：

• The episode was a huge embarrassment for all concerned.这段小插曲令所有有关人员都感到非常尴尬。
• This episode remains sharply engraved on my mind.这段经历至今仍深深地铭刻在我的心中。

2 lottery   

n.抽彩；碰运气的事，难于算计的事

参考例句：

• He won no less than ￡5000 in the lottery.他居然中了5000英镑的奖券。
• They thought themselves lucky in the lottery of life.他们认为自己是变幻莫测的人生中的幸运者。

3 revival   

n.复兴，复苏，（精力、活力等的）重振

参考例句：

• The period saw a great revival in the wine trade.这一时期葡萄酒业出现了很大的复苏。
• He claimed the housing market was showing signs of a revival.他指出房地产市场正出现复苏的迹象。

4 jack   

n.插座，千斤顶，男人；v.抬起，提醒，扛举；n.（Jake）杰克

参考例句：

• I am looking for the headphone jack.我正在找寻头戴式耳机插孔。
• He lifted the car with a jack to change the flat tyre.他用千斤顶把车顶起来换下瘪轮胎。

5 reference   

n.提到，说到，暗示，查看，查阅

参考例句：

• We spent days going through all related reference material.我们花了好多天功夫查阅所有有关的参考资料。
• I like to have my reference books within my reach.我喜欢把参考书放到伸手可取的地方。

6 canyon   

n.峡谷，溪谷

参考例句：

• The Grand Canyon in the USA is 1900 metres deep.美国的大峡谷1900米深。
• The canyon is famous for producing echoes.这个峡谷以回声而闻名。

7 profound   

adj.深奥的，造诣深的；深度的，极度的

参考例句：

• I give you my profound thanks for saving my life.我对您的救命之恩深表谢意。
• He has a profound knowledge of mathematics.他数学知识渊博。

8 grammatical   

adj.语法的，符合语法规则的

参考例句：

• His composition is excellent except for some grammatical mistakes.他的作文写得很好，只有几处语法错误。
• He can barely form a grammatical sentence.他几乎造不出合乎语法的句子。

9 specified   

adj.特定的

参考例句：

• The architect specified oak for the wood trim. 那位建筑师指定用橡木做木饰条。
• It is generated by some specified means. 这是由某些未加说明的方法产生的。