下功夫[xià gōng fu]
put in [devote] time and energy; concentrate one's efforts:
例：要想学习好, 就得下功夫。
If you want to study well, you must put in a lot of effort.
不下功夫, 你就什么也得不到。
Nothing can be obtained without efforts.
1. make great efforts：地毯业carpet growth | 下功夫make great efforts | 绚丽多彩colorful look