to contract muscles; to press down; to strain
To contract one's muscles trying to give birth to a baby.
To contract one's muscles trying to empty one's bowels.
(thông tục) to be delivered of ...
To try hard vainly to be delivered of a sentence.
to exert oneself
To exert oneself to deliver; nisus fomativus
to do something with great difficulty
To write a sentence with great difficulty/effort