s hurdler Liu Xiang was disqualifieddue to false start in the 60-metre event, _____ his rival Dayron Robles of Cubaan easy win of 766 seconds

very strict quality control and anything imperfect is ____, so customersfeel secure about our products

______ do you go for a trip with your family — About once a year.

下列各句中，没有语病的一句是

Ascientist who can speak English is in closer touch with those of othercountries than ______ who doesn’t.