－What makes him so happy?

－________ a prize in the computer contest．

Because of winning

For he won

Winning

He won

－What are you busy doing these days?

－________ the final examinations．

To prepare myself for

Preparing myself for

To make preparations for

Myself preparing

－You were brave enough to raise objections(反对)at the meeting．

－Well, now I regret ________ that．

to do

to be doing

to have done

having done

－Why not take this road?It's a short cut．

－I'm afraid we can't．It ________．

is repaired

is being repaired

has repaired

is repairing

－Have you moved into the new house?

－Not yet, the rooms ________．

are being painted

are painting

are painted

are being painting

－The window is dirty．

－I know．It ________ for weeks．

hasn't cleaned

didn't clean

wasn't cleaned

hasn't been cleaned

－Do you like the material?

－Yes, it ________ very soft．

is feeling

felt

feels

is felt

－Will you go to the party?

－Of course I will if ________．

having invited

invited

I was invited

I will be invited

－Where have you been, Mr．White?

－I ________ to the evening party．

has been inviting

had been inviting

was invited

am invited

－Have the students started to work on their experiment?

－Yes, it ________．

has done

is going to be done

is being done

is to be done