完成时态
Remember that the tense of a verb refers to the time of the action or state of being.
动词的时态指的是行为或状态所处的时间。
The perfect tenses expresses action that is already completed.
完成时态表示已经完成的动作。
The present perfect tense expresses a present action that began in the past and is now completed in the present.
现在完成时态表示开始于过去，现在已经完成的行为。
The past perfect tense expresses an action that began in the past, was completed in the past before something else occurred.
过去完成时态表示在其他事情发生前开始于过去，并在过去完成的行为。
The future perfect tense expresses an action that will be completed by some point in the future.
将来完成时态表示将来某个时间点完成的动作。
Examples of The Perfect Tense:
完成时态的例句：
To form the perfect tenses, you must use auxiliary verbs.
完成时态需要使用助动词。
Present Perfect-Present tense of have + past participle
现在完成时态-have的现在时态+过去分词
Past Perfect-Past tense of have + past participle
过去完成时态-have的过去时态+过去分词
Future Perfect-Will or shall + have + past participle
将来完成时态-Will 或shall + have + 过去分词
It is easier to understand the perfect tenses by looking at some examples:
下面的例句会帮助理解完成时态：
1) I have put the money in the machine. (present perfect)
1)我已经把前放进机器了。(现在完成)
2) I had finished my homework before mom called me for dinner. (past perfect)
2)妈妈叫我吃饭前我就写完作业了。(过去完成)
3) By the time the show is over, Marie will have danced for 40 minutes. (future perfect)
3)演出结束时，Marie已经跳了40分钟舞了。(将来完成)
4) The class has been outside for recess. (present perfect)
4)学生已经去外面休息了。(现在完成)
5) Jeff tried to hide the vase because he had broken it. (past perfect)
5)Jeff 试图把他打碎的花瓶藏起来。(过去完成)
6) By the time I am 18, I will have saved over $2,000. (future perfect)
6)我到18 岁时，就会有2000美元存款了。(将来完成)
7) My sister has taken martial arts lessons for six years. (present perfect)
7)我姐姐已经学了6年武术了。(现在完成)
8) I had watched almost all of the show before the power went off. (past perfect)
8)断电前，我几乎把所有的演出都看完了。(过去完成)
9) Do you think the lunchroom will have cooked enough pizza for all of us? (future perfect)
你认为午餐会准备充足的比萨饼给所有人吃吗?(将来完成)
10) Will had won the race every year until this year. (past perfect)
10)Will在今年前的每年都会赢得比赛。(过去完成)
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