This problem may lead to more serious ones if ____ unsolved.
27.—What did you ______ while in college? —English, politics and economics.
26.I called Nancy many times but couldn't get through.Someone ______ on the phone all the time!
25.How convenient the public transportation is! There ______ be any difficulty traveling around.
24.—I just heard you had an adventure in the desert. —We lost our way and ______ made matters worse was that our jeep broke down.
23.______ is reported, a new town has been built on the ruins left by the big earthquake.