【C20】A．whichB．thatC．whetherD．when

A．whichB．thatC．whereD．wherever

【C8】A．whichB．thatC．whatD．when

Please pause_____there is a semi－colon.A．in whichB．thatC．whetherD．where

I dont doubt_____he can finish the task on time.A．whyB．thatC．whetherD．when

I doubt_____they can swim across the river.A．whyB．thatC．whetherD．when

【27】A.whichB.thatC.whereD.when