台Taivo A Taiwan Mandarin dictionary

艱鉅

jiānjù

ㄐㄧㄢㄐㄩˋ

Simplified 艰巨

1(of a task, mission or responsibility) extremely difficult; challenging; demanding

Example

我老闆把艱鉅的任務指派給了我。

wǒ lǎobǎn bǎ jiānjù de rènwu zhǐpài gěi le wǒ

My boss assigned the hard job to me.

Keep 艱鉅 and it comes back until you know it.