I can never forget the days _____ we worked together and the days _____ we spent together.A. when; which B. which; when C. what; that D when; when
The best way to make a kid to be independent is to put him in a position _______ he has no one else to refer to .
They are still very cautious about ________ side effect the new medicine will bring about, although the experts have tried it on about 2000 patients.
His opinion was such a good one _________ his family all agreed to accept.
_____ is known to us all that the 2012 Olympic Games will take place in London.
_______ on your study, and you will make greater progress.