A professor, as well as several students, ________ in the lab.

[　　]

A．are doing experiments

B．is doing experiments

C．have been doing experiments

D．has been done experiments

What they need most ________ and they feel very happy.

[　　]

________ that a decision will be made before the end of the year.

[　　]

A．It's quite likely　　　　   B．It's like

The clever boy made a hole in the wall, ________he could see what was going on inside.

[　　]

I have bought two ballpens, ________writes well.

[　　]

Do you know the reason ________she got so angry yesterday.

[　　]

During the days ________, he worked as a servant at the Brouns.

[　　]

The knife _______we used to cut the bread is very sharp.

[　　]

________ you give me is ________I like.

[　　]

The new Science Building will be completed ________.

[　　]

A．after a year and a half

B．in a year and a half

C．afetr one and a half years

D．in one and a half year