【C5】A．thatB．thisC．whichD．it

【C15】A．thatB．somethingC．whichD．nothing

_____________ 查看材料A.whereB.thisC.whichD.that

【C19】A．thatB．thisC．whichD．what

【C2】A．thatB．in whichC．whichD．what

【C18】A．thatB．thisC．itD．I

You will see to______the engine does not get out of order.A．it thatB．thatC．whichD．whether