---I don’t know when _____ tomorrow. ---I will call you as soon as he_____.

A.as

B.why

C.which

D.when

There are so many dresses there that I really don't know ______ to choose.

A) whether B) when C) which D) why

A.A.the United States

B.B.the country

A.environment

B.accumulation

C.existence

D.evidence

A.I can

B.I will

C.I know

I don‘t know when she ___ back, but give her the message if she comes in before two.

A、is

B、will be

C、has been

D、was

come;I don’t know when my fther ______bck , but I’ll tell you when he ______bck.comes; comes; B．come;come C．come; will come D．will come; comes

A．comes; comes;

B．come;come

C．come; will come

D．will come; comes

ome; coI don’t know when he ___. But when he ___ bck, I’ll let you know.comes ; will come B．will come; comes C．comes;comes D．will come; will come

A．comes ; will come

B．will come; comes

C．comes;comes

D．will come; will come

A.I don’t know

B.It’s been delayed one hour

C.You have to be patient

D.Don’t ask me

A. When did you come back from Australia？

B.don’t know

C.not know

D.didn’t know

E.wasn’t know

A.none

B.neither

C.each

D.all