4 sentences

1. 她主攻京剧中的青衣行当。

   tā zhǔ​gōng Jīng​jù zhōng de qīng​yī háng​dang.

   She specializes in the 'Qingyi' role in Peking Opera.

   Source: Dong Chinese Dictionary

2. 生、旦、净、丑是京剧的四大行当。

   shēng, dàn, jìng, chǒu shì Jīng​jù de sì dà háng​dang.

   Sheng, Dan, Jing, and Chou are the four main role categories in Peking Opera.

   Source: Dong Chinese Dictionary

3. 他从小就跟着父亲学习木匠这个行当。

   tā cóng xiǎo jiù gēn​zhe fù​qīn xué​xí mù​jiàng zhè​ge háng​dang.

   He has been learning the trade of carpentry from his father since he was a child.

   Source: Dong Chinese Dictionary

4. 在某些地下场所，有人专门从事做鸭的行当。

   zài mǒu​xiē dì​xià chǎng​suǒ, yǒu rén zhuān​mén cóng​shì zuò​yā de háng​dang.

   In some underground establishments, some men work as male prostitutes.

   Source: Dong Chinese Dictionary