----- In recent years, problem of global warning has been very serious. ------Th
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----- In recent years,___ problem of global warning has been very serious.
------That’s right. People are facing ____ number of natural disasters now.
A. 不填; B. a; the C. the; a D. a; a
试题答案
C
解析:
考查冠词。全球变暖的问题是特指，a number of，许多，为固定表达。