These three characters all have the mouth radical (口 kǒu) on the left.

吃 Chī 'eat'

喝 Hē 'drink'

唱 Chàng 'sing'


These are rarely used on their own; they usually have objects:

吃饭 chī fàn literally 'eat rice', but actually just 'eat'

喝水 hē shuǐ 'drink water'

唱歌 chàng gē literally 'sing a song', but actually just 'sing'