在 + 多个/Number + 战线 + Verb
The noun 战线 (zhànxiàn) means 'battle front,' 'front line,' or 'war front.' It combines 战 (war, battle) with 线 (line). It can refer to a literal military front or be used figuratively to describe different areas of effort or conflict.
部队已经在东部战线部署了更多兵力。
bùduì yǐjīng zài dōngbù zhànxiàn bùshǔ le gèng duō bīnglì.
The troops have deployed more forces on the eastern front.
我们需要在环保战线上投入更多精力。
wǒmen xūyào zài huánbǎo zhànxiàn shàng tóurù gèng duō jīnglì.
We need to put more effort into the environmental front.
前线记者发回了来自战线的最新报道。
qiánxiàn jìzhě fāhuí le láizì zhànxiàn de zuìxīn bàodào.
Frontline reporters sent back the latest reports from the front.