一口吃不成胖子

yī kǒu chī bù chéng pàng zi

lit. you cannot get fat with only one mouthful (proverb)

fig. any significant achievement requires time, effort and persistence

one

kǒu

mouth

chī

variant of 吃[chi1]

no; not so

chéng

short name for Chengdu 成都[Cheng2 du1]

pàng

fat

zi

noun suffix, as in 椅子[yi3 zi5] "chair"