I often fall asleep when reading.

　　我經(jīng)�？磿�(shū)時(shí)候睡著(zhù)。

　　And then, you fall asleep.

　　然后，你就睡著(zhù)了。

　　I couldn't fall asleep last night.

　　昨晚我無(wú)法入睡。