I suppose they have known about it ,(

I suppose they have known about it ,( I suppose they have known about it,_____ I suppose nobody knows about it,_____?a.do i b.do they c.dos It s____ that they have known it I have known nothing about everything是什么意思? had i known it ,i would have.. I suppose nobody knows about it的反义疑问句是什么? 1.＿＿＿have already known about it. i suppose you have done it 改为否定句 They _____ about it,I'm sure they didn't know.A.must have kn Had known it earlier,I would not have gone back! What I have known?