Correct

开火

/ kāihuǒ / 
Strokes

Definition

to open fire

Example

As a Verb

open fire on

1
Qiánxiàn
前线
yǐjīng
已经
kāihuǒ
开火
le
了
  
。

Fighting has started at the front line.

2
Liǎng
两
zhī
支
jiànduì
舰队
xiānghù
相互
měngliè
猛烈
kāihuǒ
开火
  
,
zhízhì
直至
huánghūn
黄昏
  
。

The two fleets pounded away at each other until nightfall.

3
Jīqiāng
机枪
cóng
从
yǐnbì
隐蔽
de
的
zhèndì
阵地
kāihuǒ
开火
  
。

A machine gun opened up from a concealed position.

4
Zhǔnbèi
准备
  
!
Kāihuǒ
开火
  
!

Ready, fire!

As a Verb

attack

5
Huìshàng
会上
jǐ
几
ge
个
rén
人
tóngshí
同时
xiàng
向
tā
他
kāihuǒ
开火
  
。

Several people attacked him at the meeting.