In fact, parallel constructions in Chinese are more likely to have a structural cohesion, similar to English sentences like ‘The sooner, the better’,‘First come, first served’, and so on. Under such circumstances no conjunctions or conjunctives are needed. For example,
活到老,学到老。
Huó dào lǎo,xué dào lǎo。
It is never too old to learn. (lit. live till old, learn till old)
种瓜得瓜,种豆得豆。
Zhǒng guā dé guā,zhǒng dòu dé dòu。
As a man sows, so shall he reap.
(lit. Grow melons and you get melons; grow beans and you get beans.)
不入虎穴,焉得虎子。
Bú rù hǔ xué,yān dé hǔ zǐ。
Nothing ventured, nothing gained.
(lit. If you don’t go into the tiger’s lair, you can’t capture the tiger cub.)
天下无难事,只怕有心人。
Tiān xià wú nán shì,zhī pà yǒu xīn rén。
Where there’s a will, there’s a way.
(lit. There is nothing difficult under heaven as long as one has the heart to overcome it.)
The above are established sayings, but sentences like them can be readily coined as long as the two adjacent parts have a parallel structure or rhythm and contain a similar number of words.
[1] Yip, P. C., Rimmington, D., Xiaoming, Z., & Henson, R. (2009). Basic Chinese: a grammar and workbook. Taylor & Francis.