cat – mou
Written as māo or mao
To remember that cat is pronounced mou (mao) in Mandarin Chinese, use the following mnemonic:
The cat chased the mouse (mou).

Tones
Mou (mouse) is a 1st tone with — as an accent.
Associate mouse, a 1st tone, with a string or tie or tying or knot. See Tones and Mnemonics.

The mouse had a long straight tail.
Remember
mou = 1st tone = —