Working off her anger!

Mr. Wang and his wife always quarrel. Mr Wang found that everytime Each time, after their quarrel, his wife went to the bathroom. washroom [Though not exactly wrong, in your home, it is called the bathroom.  A washroom is a euphemism used for public facilities such as in a hotel, shopping mall etc.] He felt curious and asked.

"Why did do you go to washroom our bathroom after our spat contention [too formal for a joke] every time?" Mr wang asked.

"Well, I just to calmed me my reply down." His wife answered.

"Then what did you do in there? in washroom?" He asked again.

 
"Scrub the toilet!"

"Doese it really can help you work off your anger?"

"Yes, of course! I always used your toothbrush."

What you wrote is not wrong but in jokes, sentences must be short so that the audience won't get bored.

Work off her anger

Mr Wang and his wife always quarrel. Mr Wang found out that everytime after quarrelling, his wife went to the washroom, he felt curious.
"Why do you always go to the washroom after contention?" Mr wang asked.
"Well, it just calmed me down." His wife answered.
"Then what do are you doing in the washroom?" He asked.
"Scrub the toilet."
"Dose it help you work off your anger?"
"Yes, of course. I always used your toothbrush."