哮喘持续状态
参考答案：哮喘持续状态：是指哮喘重症发作，持续BD h以上，经常规治疗无效者,是引起哮喘病人死亡的主要原因。
There's only one day to go. You _____finish your schoolwork by tomorrow. [ ]
A. can
B. will
C. must
D. may
—Did he work out the math problem?
—No, he thought hard, but could not ______ with a proper answer.[ ]
A. put up
B. turn up
C. show up
D. come up
