【C15】A．remainB．keepC．makeD．cause

Cooling makes the engine metals their mechanical properties.A.RemainB.to remainC.retainD.t

【C15】A．caused byB．led toC．made forD．turned to

【C15】A．avoidB．avoidingC．makeD．making

Experts hope the planes flight recorder will______the cause of the air crash.A．make sense

It may not______high income, but it can make them feel proud.A．takeB．affordC．causeD．bring

【C7】A．remainB．keepC．makeD．cause