30.This machine, ______for many years, is still working perfectly. A. after which I have looked B. which I have looked after C. that I have looked after D. I have looked after 为什么A不对 和B不一样吗

Do you knoe how to use this machine?同义句Do you know the ___ ____ use this machine? This machine is unavailable. This kind of machine ___ well.(sell) Our classroom___ every day.(clean) 改为被动语态 He ordered a washing machine by phone two days ago and ___ machine will arrive this afternoon.A.a B.an C.the D./ The machine ___(invent) many years ago. This washing machine is environmentally friendly because it uses ___ water and electricity than ___This washing machine is environmentally friendly because it uses fewer water and electricity than older 翻译 This kind of machine can p_______ music. This machine is very easy to This machine is very easy to the machine has been recovered this This is ___ ___ ___ This machine was used to cut down trees in the past (改为同义句）.This machine___ ___ ___ ___down trees in the past横线上填什么啊? Machine Machine Machine This is a very expensive machine同义句转换This is( ) ( ) ( ）machine ___ funny___ you want to make a pen with a machine in it.Have a try.A.This is;that B.That is;that___ funny___ you want to make a pen with a machine in it.Have a try.A.This is;that B.That is;that C.It's;that D.It's;what He ordered a washing machine by phone yesterday,and _____ machine will arrive this afternoon.