题目

—Lifebe very hard for people living in the north of Canada as it is very cold there in winter. —Yes, the weather there be as low as 60℃ below zero. A . must; can B . shall; must C . will; should D . has to; can 答案：A --- I’m sure Andrew will win the first prize in the final. --- I think so. He ___________ for it for months.A．is preparingB．was preparingC．had been preparingD．has been preparing