40. A series of experiments to test the new drug _______ carried out, but so far it still can’t prove to be an
effective drug.
(A) was (B) were (C) has been (D) have been
43. My office is only a five-minute walk from the MRT station, so it’s _______ taking a taxi.
(A) not worth (B) no sense in (C) no point in (D) no reason to
55. The departure dates listed in this brochure for the summer tours _______ change.
(A) look up to (B) look forward to (C) are subject to (D) are based on