现在完成时
Because of the inherent differences between Chinese and English, many English learners do not understand the use of the present perfect tense, so today we will learn together how and when to use this verb tense
由于汉语和英语之间固有的差异，很多英语学习者不了解现在完成时的用法，所以今天我们就一起来学习如何以及何时使用这个动词时态。
1. The present perfect tense can be used to express unfinished actions that started in the past and continue to the present:
1.现在完成时可以用来表示从过去开始一直持续到现在的未完成的动作
For example:
例如:
·I have lived in London for five years.
·我已经在伦敦住了五年了。
·I have known John for ten years.·
我认识约翰已经十年了。
The first sentence implies that “I still live in London", and the second sentence implies that “I still know her”.
第一句暗示“我还住在伦敦”，第二句暗示“我还认识她”。
2. Present perfect tense can also refer to a finished action in someone's life (when the person is still alive: life experience):
2.现在完成时也可以指某人生命中完成的动作(当这个人还活着的时候:生活经历) For example:
例如:
·My brother has been to China three times.
我哥哥去过中国三次了。
·Bob has never travelled by boat
鲍勃从未坐船旅行过。
These two sentences are talking about the life experience of “my brother" and“Bob”and they are still alive.
这两句话讲的是“my brother”和“Bob”的生活经历，他们还活着。
3. Present perfect tense is also used to express finished events that happened in the past and the impact of the event is now continuing:
3.现在完成时也可以用来表示过去发生的已经结束的事件，而该事件的影响现在还在继续
For example:
例如:
·I have spent all of my money.
·我花光了所有的钱。
.I have lostmy keys!
·我把钥匙丢了!
Here, the present perfect tense is used to emphasize the continuing impact of the action “have spent all of my money” and“have lost my keys”, and the result is “I have no money now” and “I can't get into my house now”.
在这里，现在完成时用来强调“have spend all of my money”和“have lost my keys”这两个动作的持续影响，结果就是“I have no mor ey now”和“I canr into my house now”。
4. It can also be used with unfinished time words (this week, this month, today, this year etc.). The period time is still continuing.
4.它也可以用于未完成的时间词(本周，本月，今天，今年等)。时间还在继续。
For example:
例如:
·I've seen john this week.
·这个星期我见过约翰。
·I have eaten lots of plumps today.
·我今天吃了很多胖胖。
In these two examples, the time words have not finished yet. That is to say, in the two sentences, “this week is not over yet” and“today is not over yet".
在这两个例子中，时间单词还没有结束。也就是说，在这两句话中，“本周尚未结束”和“今天尚未结束”。
Are you now clear about the use of the present perfect tense? I hope that today's grammar knowledge is very useful for you.
现在你清楚现在完成时的用法了吗?我希望今天的语法知识对你来说能有用。
以上内容来源六分钟英语，
图片来源网络侵删。