例如：Have you found your pen yet？你已找到你的钢笔了吗？
2.现在完成时的"未完成用法"
现在完成时的"未完成用法"指的是动作开始于过去某一时刻，一直延续到现在，或可能还要继续下去。
例如：He has lived here since 1978.自从1978年以来，他一直住在这儿。(动作起始于1978年，一直住到现在，可能还要继续住下去。)
I have been in the army for more than 5 years.我在部队已经呆了五年多了。(动作开始于5年前，一直延续至今，有可能还要继续下去。)
此种用法的句中常需一个表示一段时间的状语(由since或for引导)，或表示与现在时刻相连的时间状语(如：up to now，so far到目前为止)等。
例如：I have heard nothing from him up to now.到目前为止我没有他的任何消息。
注意：(1)现在完成时的未完成用法只适用于延续性动词，不可用于终止性动词，即瞬间完成或延续时间很短的动词。如：come，go，arrive，leave，join，become，die等。
即时自测
用括号内所给词的适当形式填空
1. David and Mary got ________ (marry) three months ago.
2. There is less air ________ (pollute) in the countryside than in big cities.
3. My problem is that I have no ______________ (commute) with my parents.
4. Now the rivers in my hometown are much ________ (clean) than before.
5. Linda lives in the ________ (north) part of London.
单项选择
()1. How many English words ________ you ________ since last year?
A．did; learn B．have; learned C．are; learning D．do; learn
()2.—Does your aunt live ________？
—Yes. But she never feels ________．
A．lonely; alone B．alone; alone C．alone; lonely D．lonely; lonely ()3. Millie has seen the TV ________. Have you seen it ________？
A．yet; already B．already; already C．yet; yet D．already; yet ()4. Jack has worked here since he ________school.
A．leaves B．left C．has left D．was leaving ()5. —How does your uncle usually go to work?
—He ________ drive a car, but now he ________ a bike to lose weight.
A．used to; is used to ride
B．was used to; is used to riding
C．was used to; is used to ride
D．used to; is used to riding
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