_______ many times, he finally understood it．A．TaughtB．TeachingC．Having taughtD．

题型：不详难度：来源：

_______ many times, he finally understood it．

A．Taught

B．Teaching

C．Having taught

D．Having been taught

答案

解析

略

举一反三

Bush, before Barack Obama, _______ Brown a similar gift, a leather bomber jacket．

A．gave

B．have given

C．would give

D．had given

题型：不详难度：| 查看答案

The manager had fallen asleep where he ______, without undressing．

A．was laying

B．was lying

C．had laid

D．had lied

题型：不详难度：| 查看答案

---Where were you when I called at your house this morning?
---Oh, I_____ for a friend from Tokyo at the airport．

A．had waited

B．am waiting

C．have waited

D．was waiting

题型：不详难度：| 查看答案

---How can I apply for an online c

ourse?
---Just fill out this form and we______ what we can do for you．

A．see

B．are seeing

C．have seen

D．will see

题型：不详难度：| 查看答案

Merry________ as a secretary in the company for five years, but now she is a general manager of the company．

A．worked

B．has worked

C．is working

D．works

题型：不详难度：| 查看答案