1. Time complement Always before the main verb, after or before the subject:
I'm going to Shanghai tomorrow.
He always dine at seven o'clock.
2. Duration complement It follows the verb and specifies ho wlong the action lasts. There are two possible constructions depending on whether the action continues or is concluded:
I studied Chinese for two years (then stopped). (V + le + COMPL.)
I've been studying Chinese for two years. (V + le + COMPL. + le)
As in the examples above, if the verb has an object we can bring it before the verb. We can also use the construction V + COMPL. + de + O (second example):
I've been waiting for you for a long time!
I studied literature for one year.
To stress one aspect (in this case the time) of a past action, we can add the construction (shi) ... de:
