It’s impolite to read _______ letter .

The piano in the other shop will be _____, but _____.

Another drug that has helped improve people’s health is penicillin, _________ is _________ by many _________ one of the most important medicines.

Excuse me. Look at the sign: NO PARKING!—Sorry, I ________ it.

_______ it is so hot, I guess we can’t do anything until after dark.