No one is sure of the extent ________ this will affect business．
A．which B．when C．by which D．to which
Stephen Hawking believes that the earth is unlikely to be the only planet life has developed gradually．
A．that B．where C．which D．whose
You can hardly imagine the difficulty the woman had ________ her children．
A．bringing up B．bringing about C．brought up D．brought about
I was late this morning because my alarm o’clock failed to _______．
A．go out B．go away C．go off D．go without
If caught ________ in Singapore, the person is definitely subject to heavy fines．
A．litter B．littered C．to litter D．littering
The living room is clean and tidy, with a dining table already _______ for a meal to be cooked．
A．laid B．laying C．to lay D．being laid
