A medicine may help with your illness, but it may make you , so you must be careful not to drive a car after taking such a medicine.

You’ve dropped ________ “s” in the word “necessary”.— Oh, ________ letter “s” is doubled.

Daming didn’t take a photo in the museum. I didn’t, _______

How about the pollution in the countryside?－Luckily, it’s not as serious as _______ in the big cities.

There are two books _____the sofa. [ ]