题干
— The earthquake in Wenchuan in 2008 killed people.
— We were sad to hear that.
A：thousands
B：thousands of
C：thousand of
D：two thousand of
答案(点此获取答案解析）
B
— The earthquake in Wenchuan in 2008 killed people.
— We were sad to hear that.
A：thousands
B：thousands of
C：thousand of
D：two thousand of
< x <
}，则a + b的值为 （ ）