介詞after+名詞；
介詞after+動(dòng)名詞；
介詞after+相當(dāng)于名詞的短語或從句；
連詞after+時(shí)間狀語從句.
如：
He went to school after eight. (介詞+名詞）
After waiting for a long time, he went away. (介詞+動(dòng)名詞）（注：動(dòng)名詞相當(dāng)于一個(gè)名詞.）
He began his school after a long wait.（介詞+名詞性短語）（注：名詞性短語相當(dāng)于一個(gè)名詞）
After _what__ seemed an endless wait, it was her turn to enter the personnel manager’s office.(介詞+名詞性從句）（注：what引導(dǎo)的從句都是名詞性從句,這種從句相當(dāng)于于一個(gè)名詞.）
He went to school after the clock stuck eight. (連詞+時(shí)間狀語從句）
此例不好改成連詞after引導(dǎo)的時(shí)間狀語從句,硬要改而且意思不能有變的話,可以加一個(gè)插入語：
After she waited for a long time, one that seemed endless, it was her turn to enter the personnel manager’s office.
祝你學(xué)習(xí)進(jìn)步,更上一層樓! (*^__^*)
不明白的再問喲!請(qǐng)記得采納,多謝!我已經(jīng)在例句中說了，這個(gè)after是介詞，后面接了一個(gè)名詞性從句。網(wǎng)上說如果是連詞，從句的時(shí)態(tài)常用完成體。這種說法不太靠譜，after引導(dǎo)的時(shí)間狀語從句也常用一般過去時(shí)，甚至也可用一般現(xiàn)在時(shí)、一般將來時(shí)。