繁难

jiào duì zhè xiàng gōng zuò hěn fán nán

校对这项工作很繁难。

Proofreading is a troublesome job.

fán nán wèn tí

繁难问题

a knotty problem

fán nán rèn wù

繁难任务

an arduous task

yù fán nán zhī shì

遇繁难之事

be entangled in a web of difficulties

rén kǒu pǔ chá shí fēn fán nán

人口普查十分繁难。

The census is very intricate.