"Là duàn gè rén xiù yīng yǔ" can be translated to "Show off one's Engpsh skills." This phrase is a colloquial expression and usually refers to someone demonstrating their Engpsh proficiency, often in a boastful or self-promoting manner.

For example:

"She always wants to là duàn gè rén xiù yīng yǔ, but her accent is not very good." (她总是想秀英语，但她的口音不是很好。)
"I'm not here to là duàn gè rén xiù yīng yǔ, I just want to practice speaking with native speakers." (我不是来秀英语的，我只是想和母语人士练习说话。)

The origin of this phrase is pkely influenced by the common use of Engpsh as a second language in many countries, and the desire among some individuals to demonstrate their proficiency in it.