Be (as) stubborn as a mule phrase informal simile
Be extremely stubborn
Mina is as stubborn as a mule. She doesn't like broccoli and she won't eat it even if you pay her.
She won't do what you tell because she's as stubborn as a mule.
The boy is as stubborn as a mule. He is bent on buying that motor.
Used to describe someone who is realistic and determined
The verb "be" should be conjugated according to its tense.
Used to express one's feelings when facing a bad situation
Man, my life really sucks. Life's a bitch and then you die.