HSK C3/W3/V5
Correct

增

/ zēng / 
Strokes

Definition

to increase/to expand/to add

Example

As a Verb
increase; gain; add
1
Yǒuzēngwújiǎn
有增无减

keep increasing

2
Zēngpài
增派
fēijī
飞机

send additional planes

3
Zēngbīng
增兵

throw in more troops; reinforce an army; augment one's forces