While he ________ his homework , his mother came in.A．doesB．didC．was doingD．do

题型：不详难度：来源：

While he ________ his homework , his mother came in.

A．does

B．did

C．was doing

D．do

答案

解析

while 引导的时间状语从句，从句往往用进行时态，故选C

举一反三

My friend _______ well in English , so she often helps me with my projects .

A．do

B． does

C．is doing

D．are doing

题型：不详难度：| 查看答案

Look! Who ___________ on the blackboard?

A．writes

B．is writing

C．are writing

D．writing

题型：不详难度：| 查看答案

---Listen! Who ______ in the next room?
---I think Sam is.

A．sing

B．sings

C．singing

D．is singing

题型：不详难度：| 查看答案

Look! The students ________ basketball on the playground .

A．play

B．playing

C．are playing

D．is playing

题型：不详难度：| 查看答案

—My sister looks very upset. What should I do?
—I think she happy if you ____a surprise party for her .

A．is; have

B．will be; will have

C．is; will have

D．will be; have

题型：不详难度：| 查看答案