－Do you mind if I open the window?

－________ I feel a bit cold．

A．Of course not．

B．I'd rather you didn't．

C．Go ahead．

D．Why not?

Parents are taught to understand ________ important education is to their children's future．

A．that

B．how

C．such

D．so

We cannot figure out ________ quite a number of insects, birds, and animals are dying out．

A．that

B．as

C．why

D．when

The road is covered with snow．I can't understand ________ they insist on going by motorbike．

A．why

B．whether

C．when

D．how

The chairman thought ________ necessary to invite Professor Smith to speak at the meeting．

A．that

B．it

C．this

D．him

It is widely accepted that young babies learn to do things because certain acts lead ________ to．

A．rewards

B．prizes

C．awards

D．results

Recently I bought an ancient Chinese vase, ________ was very reasonable．

A．which price

B．the price of which

C．its price

D．the price of whose

I don't know the reason ________ you were absent fron the meeting, but I'm sure that someone will tell me the reason ________ you haven't told me．

A．why, that

B．that, why

C．because, which

D．of which, that

Only Timmy and his brother Jimmy at home, for ________ to their grandparents'．

A．went their parents

B．did their parents go

C．did their parents went

D．their parents went

It's impolite to laugh at the people who are ________．

A．out of trouble

B．in trouble

C．get into trouble

D．in the trouble