It seems ________ it is going to rain．

as

like

as if

just as

One of the advantages of living on the top floor of a highrise is that you can get a good ________．

sight

scene

view

look

It will be very dangerous to swim or dive in the ________ of submarine activity．

zone

region

district

The drug had an immediate ________ on the pain．

affect

effect

My cousin went to Canada two yours ago．He ________ there for a few months and then went to America．

worked

would work

would be working

has been working

Look out!Don’t get too close to the house ________ roof is under repair．

whose

which

of which

what

Once lost, ________．

it is hard to get such a chance again

to get such a chance will be difficult

one can never get such a chance again

such a chance might never come again

The idea for the new machine came to Mr．Baker ________ to his invention recently．

while devoting

while devoted

while he was devoted

while devoting himself．

He has got himself into a dangerous situation ________ he is likely to lose control over the plan．

where

which

when

why

It is fairly common in Africa for there ________ a group of expert musicians surrounded by others who also join in the performances．

being

to be

be

is