Editors note: This is the third of a four-part series on verb tenses. Click here to see part one . See the others in Related Stories.
编者注：这是动词时态系列四部分中的第三部分。单击此处查看第一部分。请参阅相关故事中的其他内容。
In this week’s episode 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.
在本周的日常语法中，我们将帮助您理解简单过去时和现在完成时之间的区别。英语学习者经常混淆这两种动词时态。
Let’s start with an example. Can you tell the difference between these two sentences?
让我们从一个例子开始。你能说出这两句话的区别吗？
Sentence one: I saw the movie.
第一句话：我看过这部电影了。
Sentence two: I have seen the movie.
第二句话：我看过这部电影。
Sentence one uses the simple past tense. Sentence two uses the present perfect tense.
第一句使用简单过去时。第二句使用现在完成时。
“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.
“我看过电影”和“我看过电影”都指过去完成的动作。但有一个重要的区别：“我看过这部电影”表明您在过去的某个特定时间看过这部电影。 “我看过这部电影”表明您在过去的某个未知时间看过这部电影。
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.
使用简单过去时来谈论在特定时间发生的已完成的动作。例如，“我昨晚和朋友出去了。”副词“昨晚”不是必需的，但它确实有助于澄清事件发生在特定时间。
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.
这是最简单的部分。现在我们来谈谈现在完成时。您可以使用“have”或“has”后跟动词的过去分词形式来形成现在完成时。
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.
例如，“我已经大学毕业了。”现在完成时让英语学习者感到困惑，因为它指的是过去的动作。它也被称为“现在完成时”，因为说话者用它来强调过去事件对现在的重要性。 “我已经大学毕业”这句话强调了过去事件——毕业——的现在效果。毕业的确切时间并不重要。
There are four more common situations that require the present perfect.
还有四种常见情况需要现在完成时。
First, it can express a repeated action. When an action happened more than one time in the past, use the present perfect. For example,
首先，它可以表达重复的动作。当某个动作在过去发生多次时，请使用现在完成时。例如，
“I have seen the movie three times."
“这部电影我已经看了三遍了。”
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,
其次，通常将现在完成时与“for”和“since”等词一起使用。 “for”和“since”是副词，表示活动的持续时间。他们回答“多长时间？”的问题。例如，
“I have studied English for a long time."
“我学英语很长时间了。”
Third, the negative adverb “never” requires the present perfect. You can say,
第三，否定副词“从不”需要现在完成时。你可以说，
“I have never been to France.”
“我从来没有去过法国。”
You would not say,
你不会说，
“I did never go to France.”
“我从来没有去过法国。”
Finally, when asking a question in the present perfect, use “ever,” as in,
最后，当用现在完成时问问题时，使用“ever”，例如，
“Have you ever won the lottery?”
“你中过彩票吗？”
Here’s a tip: pay close attention to adverbs. Adverbs give hints, or clues, about which verb tense you should use.
这里有一个提示：密切注意副词。副词提供有关您应该使用哪种动词时态的提示或线索。
A good way to practice the present perfect is to ask an English-speaking friend if he or she has ever done something.
练习现在完成时的一个好方法是询问说英语的朋友他或她是否曾经做过某事。
“Have you ever flown in an airplane?”
“你坐过飞机吗？”
“Have you ever seen the Grand Canyon?”
“你见过大峡谷吗？”