Can I smoke here?-No，at no time ________ in the reading room.[ ]

The two girls _____ how to dance one month ago and now they can dance well.

We must __________ that the experiment iscontrolled as rigidly as possible.

An e-book is usually much______ than an ordinary paper book.

Would you tell me__________you want your tea , with sugar or milk ?—Sugar , please .