－Can you describe ________ it happened?

－Yes, I was riding on my bike ________ a car knocked me down from behind．

when; as

how; as

how; when

how; while

－Mum, where is my raincoat?

－Oh, I forgot to tell you．It ________ behind the kitchen door．

would hang

has hung

is hanging

hung

－Will you please make yourself ________ to us, please?

－I'm the honorary chairman of the committee．

know

to know

knowing

known

－I wonder if you could go with me to the supermarket．

－Don't disturb me．I ________ my experiment report all the morning and haven't finished yet．

write

was writing

have written

have been writing

－Where's your homework?

－________．

It's been handed in

I would hand it in

It'd been handed in

I had handed it in

－Have you finished the book?

－No．I've read up to ________ the children discover the secret cave．

which

what

that

where

－How about eight o'clock outside the cinema?

－That ________ me fine．

fits

meets

satisfies

suits

－I must apologize for ________ ahead of time．

－That is all right．

letting you not know

not letting you know

letting you know not

letting not you know

－I have passed the driving test!

－________!

Go ahead．

Come on!

Absolutely!

Congratulations!

－Does it rain a lot in this area?

－________, it hardly ever rains; the climate is like that of a desert．

What's worse

In other words

On the contrary

As a result