He was so angry at all _____ she was doing _____ he walked out.
With a good ______ of both Chinese and English,she had an advantage over the other interviewees.
He stayed up too late every night,______ to catch up with his classmates.
Exercise is _______ as any other to lose unwanted weight.
______known to us,_______ increasing number of students are buried in their studies.
Not until _____,_______the diffiult problem.