The two / both (二者/两者)

Structure (referent A, referent B) + 二者/两者 + predicate

二者 (èr zhě) and 两者 (liǎng zhě) are the formal anaphor for TWO already-mentioned referents: "both", "the two elements". They match the colloquial 两个 / 两样 but belong to written and essayistic register, where they sum up two compared things in a single word. They show up in set frames like 二者缺一不可 ("neither of the two can be missing") or 二者兼顾 ("to attend to both at once"), and often pair with 前者…后者… to unpack the reference. 二者 and 两者 are nearly interchangeable; 二者 sounds slightly more formal and arithmetic.

Examples

理lǐ论lùn与yǔ实shí践jiàn，二èr者zhě缺quē一yī不bù可kě。
Theory and practice — neither of the two can be missing.
效xiào率lǜ与yǔ公gōng平píng，二èr者zhě必bì须xū兼jiān顾gù。
Efficiency and fairness: both must be taken into account together.
两liǎng者zhě之zhī间jiān存cún在zài着zhe本běn质zhì的de区qū别bié。
Between the two there is an essential difference.
在zài质zhì量liàng和hé速sù度dù之zhī间jiān，两liǎng者zhě很hěn难nán兼jiān得dé。
Between quality and speed, it's hard to have both at once.

Levels are indicative: they follow the standard Chinese Grammar Wiki (AllSet Learning) progression, not an official HSK 3.0 mapping. We never assign levels by eye.

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