It is every citizen's duty to _____ our country when she is attacked by the enemy．
A．approach B．defend C．support D．preserve
—How long have you been here?
—___ the end of last year．
A．Since B．At C．By D．In
It rained for several weeks, completely ____ our holiday．
A．ruined B．ruining C．to ruin D．ruin
Xiamen Xiang'an Tunnel, _____ is the first undersea tunnel built in mainland China, opened to traffic on April 26th．
A．that B．what C．where D．which
A survey of the opinions of experts ____ that drinking a glass of hot milk before going to bed helps one sleep well．
A．shows B．show C．is showing D．have shown
—Which of the two iPods do you prefer?
—To tell you the truth, I don't like _____ of them．
A．both B．either C．none D．neither
