1.The number of air crashes that ________in developing countries ________increasing.
A.happens;is B.happen;is
C.happens;are D.happen;are
答案 B [air crashes后定语从句的谓语动词用复数;“the number of +复数名词”作主语时,谓语动词用单数。]
2.Eric even didn't have ________common sense to dial the number 119 when ________fire broke out.
A.a;the B.a;/
C./;the D.the;a
答案 D [第一空特指“紧急情况下拨火警电话”这一常识;第二空泛指“一场火灾”。 ]