Which sign means you can't drop litter?

A．

B．

C．

D．

My grandma likes Beijing Opera, ________ she can't sing it well．

A．so

B．and

C．or

D．but

If she ________ there, call somebody else．

A．doesn't be

B．is

C．isn't

D．won't be

There ________ a wonderful TV play on TV tonight．

A．will have

B．is going to be

C．is going to have

D．has

It's difficult for the Greens to keep the flat ________ with four children．

A．clean

B．cleaning

C．cleaned

D．cleans

There is ________ cloud in the sky．I'm afraid it'll be ________ rainy．

A．too much, too much

B．much too, much too

C．too much, much too

D．much too, too much

It's ________ to say “May I come in?” before you come into the teachers' office．

A．much polite

B．more politer

C．more politely

D．more polite

You're a little weak in English．You should spend ________ reading English every morning．

A．some times

B．sometime

C．some time

D．sometimes

There're ________ students in our school．They're all working hard．

A．three thousand

B．three thousands

C．thousand of

D．three thousands of

Don't read ________ the sun．It's bad ________ your eyes．

A．under, for

B．under, of

C．in, of

D．in, for