e.g.They are looking for some jobs to
raise babies.(动词不定式做宾语补足语)
The government promised to implement a new system(动词不定式做宾语)
The girl waiting outside the door is my headmaster.(现在分词做定语)
e.g.Can you understand me?
Will he come to school tomorrow?
He ought to have a better performance.
She should pay the bill .
I may have met him before.
You must do some exercises.