—When ________ again?—When he ________, I'll let you know.
He is a poorly learned man, but he acts as though he _____.
—I don’t suppose Jimmy could have done well in the mid-term exam last week,______? `--- ______ he almost failed in the exam.
It is strange that such a thing ______ in your school.
As is often pointed out, knowledge is a two-edged weapon which can be used ________ for good or evil.
Urban crowdedness would be greatly relieved if fares ________ on public transport were more reasonable.