join是持续性动词吗?怎样的词才称为持续性动词呢?请详细举个例说明一下.

不是.
He joined the club three years ago.----He has been in the club for three years.-----He has been a member of the club since three years ago.
瞬间动词改成延续动词
borrow---keep
buy----have
begin---be on
有些动词本身是延续的：如：wait,run,sleep