Legend has ______ that CaoCao, King of Wei kingdom in the Three Kingdoms period, built 72 tombs to confuse tomb diggers.
A. it B. this C. them D. itself
It is high time we ______ awareness of environmental protection.
A. promoted B. would promote C. shall promote D. had promoted
How can they learn anything useful ______ they spend all their spare time playing online games?
A. while B. unless C. although D. when
______ is it that metals plays such an important part in our daily life?
A. Why B. What C. Where D. When
Early this year cruel snowstorms hit southern China, great transportation problems in some areas.
A．caused B．to cause C．having caused D．causing
--- Why can’t I smoke here?
--- At no time in the meeting room.
A．is smoking permitted B．smoking is permitted
C．does smoking permit D．smoking be permitted
