---Do you know when he will come back tomorrow? ---Sorry, I don’t know. When he back, I’ll tell you.
—Your tea smells great! —It’s from India.Would you like________?
The World Health Organization has given some advice on________to protect us from being infected(感染)with H7N9.
—What do you usually help your mother________? —I often do the dishes.
It took him one hour________his homework.
The weather is too dry.Those trees need________.