Whale beachings（搁浅）_______ be caused by factors such as illness, or disorientation（迷失方向）caused by extra noise in the oceans, ______ shipping or oil and gas drilling.

–Must I return the story book tomorrow, madam?       –No, you ______ bring it here next Monday.

The public transportation is very convenient in that big city, so there ________ be any difficulty in traveling around.

Rose, you       leave your school things on the floor like this. Keep your room clean and tidy.

—I can’t stop smoking, doctor.— For your health, I’m afraid you________.