I didn't know when they ____ again.A.came B.were coming C.had come D.had been coming

I didn't know when they ____ again.A.came B.were coming C.had come D.had been coming
I didn't know when they ____ again.A.came B.were coming C.had come D.had been coming

I didn't know when they ____ again.A.came B.were coming C.had come D.had been coming
B.were coming
从句中要用故去将来时态.

a

选A

选A.came 因为前面主句用的是过去式，后面从句就要用一般现在时。所以选A