1.We need the same machine ___in your factory.
A.which is being used B.that used
C.as is being used D.as it is being used
2.The teacher asked me some questions___to my paper.
A.relative B.about C.on D.for
3.The engineer said that newly-designed engine was___the old one.
A.as twice powerful as B.powerful as twice as
C.twice as powerful as D.twice more powerful as