攻坚

gōng jiān zhàn lüè

攻坚战略

tactics for storming a fortified position

gōng jiān zhàn dòu

攻坚战斗

battle in which fortified positions are stormed

zài zhè ge xiàng mù kāi shǐ hòu zhěng gè zǔ dōu kè nán gōng jiān

在这个项目开始后整个组都克难攻坚。

The whole team has been on a steep learning curve since the project began.