问题
选择题
---Why did the teacher get angry? --- __________ what we had done the day before.
A.Because
B.Since
C.As
D.Because of
答案
答案:D
考查介词短语。because of 是介词短语,后接名词、代词或者接名词性从句。而在此处是有what引导的名词性从句,相当于一个名词,所以用because of。