一来……二来……yīlái…èrlái…

Firstly... Secondly... (Listing Reasons): 一来……二来……

Meaning: Firstly..., secondly... (listing parallel reasons or purposes)

Pattern

"一来…二来…" (sometimes extended to "三来…四来…") is a parallel enumerative structure meaning "for one thing..., for another..." or "firstly..., secondly...":
(1) It specifically explains the reasons, motives, or advantages behind a preceding decision or recommendation (e.g., 我选择步行上班，一来锻炼身体，二来节省开支).
(2) Each clause is typically concise and balanced, and the reasons are mutually complementary rather than contradictory.
(3) Compared with "首先…其次…" (which can list steps, topics, or arguments of any kind), "一来…二来…" is lighter, more rhythmic, and specifically dedicated to enumerating reasons/purposes in both speech and essays.
Do not mix "一来" with "一方面" or "其次" in the same sequence.

1
我选择步行上班，一来锻炼身体，二来节省开支。
Wǒ xuǎnzé bùxíng shàngbān, yī lái duànliàn shēntǐ, èr lái jiéshěng kāizhī.
I choose to walk to work: firstly to exercise my body, and secondly to save expenses.
2
他不想出国，一来语言不通，二来不舍得家人。
Tā bù xiǎng chūguó, yī lái yǔyán bù tōng, èr lái bù shědé jiārén.
He doesn't want to go abroad: for one thing there is a language barrier, and for another he can't bear to leave his family.
3
推荐这家餐厅，一来环境好，二来价格实惠，三来服务周到。
Tuījiàn zhè jiā cāntīng, yī lái huánjìng hǎo, èr lái jiàgé shíhuì, sān lái fúwù zhōudào.
I recommend this restaurant: firstly the environment is nice, secondly the prices are affordable, and thirdly the service is attentive.

•Specifically lists complementary reasons or purposes (can extend to 三来…); do not use for contrasting/opposing clauses.

⚠️ Common Mistakes:

•Making the clauses after 一来 and 二来 wildly uneven in length or grammatical structure.

•Using 一来…二来… to contrast two opposing aspects: use 一方面…另一方面… instead.

•Using 一来 alone without following up with 二来 (leaves the correlative listing incomplete).

Combine Vocabulary, Grammar, Reading Practice, Listening, Hanzi Writing, and Mock Exams at HSK 6 to master all skills together.