A joke with only one word

One evening by the river, Ah Q said to his new girlfriend: I can say a word to make you laugh or a word to make you hate.

Girlfriend said she didn't believe it.

At this time, Ah Q walked up to a Baha 'i dog, plopped down on his knees, and only heard a loud cry: Dad.

As a result, all the audience burst into laughter.

Ah Q turned to his girlfriend and shouted: Mom!