Tom used to come and visit me a lot on his business trip between Hong kong and ____was then Beijing A, that B .which C. where D.what
Once ____ in the forest, you ought to remain ____ you are waiting for help.
You will succeed in the end ____ you give up halfway.
____ made things worse, he said, was that his roommate never took part in any of the cleaning work.
Many things such as going abroad and owning a car, ____ impossible in the past, are now very common.
Walking exercises ____ be boring at times, but on a clear sunny morning nothing could be better.