吸吮

yīng ér zài xī shǔn mǔ qīn de rǔ zhī

婴儿在吸吮母亲的乳汁。

The baby is nursing at its mother's breast.

xī shǔn mǔ zhǐ

吸吮拇指

suck the thumb

bǎ jú zi xī shǔn gān

把橘子吸吮干

suck an orange dry

tā zài dān yōu shí réng rán huì xī shǔn dà mǔ zhǐ

她在担忧时仍然会吸吮大拇指。

She still sucks her thumb when she's worried.