“How was ______ they discovered the entrance to the underground palace?” “Totally by chance.”
A. it that B. he that
C. it when D. he which
It was totally by chance that they discovered the entrance to the underground palace.
(1) Who was it _____ saved the drowning girl?
A. since B. as C. that D. he
答案选C，被强调成分为 who，该句实为类似 It was Tom that saved the drowning girl. 这类强调句的特殊疑问句形式（即对其中的Tom 提问而得）。
(2) What is it _____ his daughter needs most?
A. what B. which C. that D. if
答案选C，被强调成分为 what，该句实为类似 It is a bike that his daughter needs most. 这类强调句的特殊疑问句形式（即对其中的a bike 提问而得）。