Safety in school has been of great conce
题型:选择题
问题:
Safety in school has been of great concern because of frequent reports about accidents _______ students got injured or killed while in school .
A.that
B.when
C.in which
D.for which
Safety in school has been of great concern because of frequent reports about accidents _______ students got injured or killed while in school .
A.that
B.when
C.in which
D.for which