PS:请写出为什么1.The old scientist has made --- in growing rice,wh

PS:请写出为什么
1.The old scientist has made ___ in growing rice,which will ___ more people in the world.
A.a breakthrough;feed on
B.a breakthrough;feed
C.a breakthrough;feed to
D.breakthrough;feed with
2.Is your house ___ now?
-Yes,it ___ a half month.
A.painting;takes B.being painted;will take
C.painted;will take D.being painted;takes
3.He made it ____ combining many others' methods.
A.with B.by C.for D.from