It is ten months since he ______ a doctor.
Laura wanted to play a joke on her father but gave herself________by laughing.
People have planted a great many trees in order to________ wind and sand in the desert.
—Which of those novels do you like most? —________.They are both expensive and of little use.
(2012年三亚高三模拟)English can help________people and make the stay in a foreign country easy and comfortable.
—The air is full of smoke and people are coughing. —It will get worse________the government does something about the pollution.