Example sentences
tā他gōng工zuò作hěn很máng忙。
He's busy with work.
nǐ你zuò做shén什me么gōng工zuò作？
What do you do?
About this word
工 is "work, labor" and 作 is "to do, to make". The two halves point at the same idea from different angles, so 工作 is a doubled-up word for work. It covers the noun and the verb alike: 我的工作 is "my job", 我在北京工作 is "I work in Beijing". 工 on its own shows up in 工人 (worker) and 工厂 (factory); 作 carries the "do, produce" sense in 作文 (essay) and 作业 (homework). One usage note: 工作 usually means salaried or office work. Physical labor leans toward 干活, and 上班 means "to go to work, to be on shift", not the job itself.
The story behind the character
工
The earliest 工 is a carpenter's square. The right-angle ruler. It meant "tool," then "the person who works." So 工 started as a ruler.
作
作 is 人 (a person) with 乍 beside it, and 乍 carries the sound. Xu Shen wrote 作, 起也, to get up, to rise. The oldest writing had only 乍, and the person was added later. Nobody agrees what 乍 first pictured, a blade cutting something or a needle sewing. From getting up it grew into doing and making. 工作 is what you get up to do.