I'd like to know what's the correct usage of the expression "for all time". In particular in this sentence: "she cried for all time" (it's about a girl who took a plane and cried during the whole flight). Thanks a lot for your attention!
"For all time" means "forever", and is used with a certain dramatic flair.
Shakespeare's genius is not just for the 17th century, it is for all time.
God is not the God of the Bible only, he is God for all time.
The situation you are using is more bounded. You might say:
She cried the whole flight. or She cried for the whole flight.
Pity the poor girl were she to cry for all time. That sounds like a Greek tragedy to me.