2021銀行校園招聘考試：英語單選題（3）
Economics, several courses of which I have taken thus far, ______ to be difficult but useful for almost all students。（ ）
A. prove
B. proves
C. have been proved
D. are proved
東吳教育參考答案解析
答案:B
解析：考查主謂一致。其中several courses of which I have taken thus far為設置的干擾項。由于主語為表示學科的單數名詞，故謂語應是單數形式。prove to be證明是，主動表被動。
