1、She apologized for ______ to attend the meeting.

　　A.her being not able B.her to be not able

　　C.her not to be able D.her not being able

　　2、______ you were busy, I wouldn't have bothered you with my questions.

　　A.If I realized B.had I realized

　　C.Did I have realized that D.As I realized

　　3、There are many kinds of metals, ______.

　　A.each having its special properties B.having its special properties

　　C.one has its special properties D.each has its special properties

　　參考答案及解析：

　　1、D　此為固定語序，sb's not doing sth.

　　2、B　典型的表示與過去事實(shí)相反的虛擬語氣句型，條件狀語從句用if+主語+過去分詞，主句用：主語+ would (not)/should(not)+過去分詞，當(dāng)省略if 時(shí)，條件從句中的had 提前。

　　3、A　本句考察獨(dú)立主格結(jié)構(gòu)。B沒有主語;逗號(hào)不能連接兩個(gè)獨(dú)立完整的句子，因此排除C，D;只能選A。句意為“金屬有很多種，每一種都有它的特性。”