本章讲解了两个知识点，一个是如何判断可数名词单数是加a还是an，另一个是有关一般疑问句和特殊疑问句的正确语序以及特殊疑问词的运用。

This episode covers the use of a/an and the way to ask general question and special question. When should we use “an” and when should we use “a” before the countable nouns? Which special words should we use when we need to ask a special question?