Correct

对子

/ duìzǐ / 
Strokes

Definition

pair of antithetical phrases/antithetical couplet

Example

As a Noun

pair of antithetical phrases/sentences

1
Duì
对
duìzǐ
对子

supply an antithetical phrase to a given phrase

As a Noun

antithetical couplet

2
Xiě
写
duìzǐ
对子

compose/write an antithetical couplet

As a Noun

pair

3
Jiéchéng
结成
hùbānghùxué
互帮互学
de
的
duìzǐ
对子

form a learn-from-each-other-and-help-each-other pair; partner with