Doctors __________ that air pollution can cause lung cancer.A. provedB. has provedC. have been provedD. have proved
If we ________ throwing garbage into the river, it will be polluted.A. will stopB. won’t stopC. don’t stopD. stop
If people really cared about environment, they ______waste into rivers.A. didn't dumpB. don't dumpC. won't dumpD. wouldn't dump
If Ha __________ the exam, she __________ to medical college.A. passes/will goB. pass/would goC. passed/will goD. pass/will g