The old house is regarded as a part of local history, so it should be ________. [ ]

Aprofessor from _______university said that he would think out _______unusual way to face the serious problem .

Which of the new books do you like better—I like ______ of them, because they’re of little use to me.

________they decide which college to go to，students should research the admission procedures

Between the two generations, it is often their different views of life and value _____ cause family conflicts.