英语：如果说做时态题的规律是看动词发生的时间,那么持续动词又该怎么判断?

延续性动词表示能够延续的动作如：learn,work,stand,lie,know,walk,keep,have,wait,watch,sing,read,sleep,live,stay等.延续性动词可以与表示时间段的状语连用.表示时间段的短语有:for+ 时间,for 2 years; since从句,since he came here; since+时间点名词,since last year,since 5 days ago; how long; for a long time等.例:He has lived here for 6 years.You can keep the book for 5 days.I stayed there for 2 weeks last year.How long did you stay there last year?