HSK 7–9 grammar · pattern
（要+）动词+就+动词+个+补语
（要）V就V个 + 补语 — if you're going to, do it properly
Pattern
+ + + + +
( ) can be left out · other words may come before, between and after
How it works
The verb is repeated across 就, and 个 introduces a complement saying how thoroughly it should be done: 要玩就玩个痛快. The speaker is rejecting half-measures — commit, or don't start.
Examples
要玩就玩个痛快。
Yào wán jiù wán ge tòngkuài.
If you're going to enjoy yourself, do it properly.
要说就说个明白。
Yào shuō jiù shuō ge míngbai.
If you're going to speak, say it plainly.
Related
See it in a story
In the app, （要+）动词+就+动词+个+补语 is underlined wherever it appears in the stories you read, and practised with sentences from them. Free.