Verb + 得/不 + 了/下/起 (advanced potential complements)

• Pinyin: de/bù + liǎo/xià/qǐ
• Formation: Verb + 得/不 + 了/下/起
• Hanzi breakdown: 了 = originally a pictograph of a child (completion); 下 = one (一) below a line (spatial descent); 起 = 走 (walk) + 己 (self), to rise up

Meaning

Advanced potential complements use 得 or 不 between a verb and a directional or resultative complement to express whether an action is possible. The three key complements are 了 (ability/capacity), 下 (fitting/accommodating), and 起 (affordability/worthiness). These structures go far beyond simple 'can/cannot' and encode nuanced real-world feasibility.

The potential complement system in Chinese is one of its most distinctive grammatical features, absent in most European languages. Verb + 得/不了 indicates whether an action can be completed or managed — often relating to quantity, time, or physical ability (e.g., 吃得了 means 'can eat it all,' 吃不了 means 'cannot finish eating'). Verb + 得/不下 focuses on spatial accommodation or capacity — whether something can fit or be contained (e.g., 坐得下 means 'can seat/fit,' 坐不下 means 'cannot fit'). Verb + 得/不起 relates to affordability or social worthiness — whether one can bear the cost or merit (e.g., 买得起 means 'can afford,' 对不起 means 'cannot face/sorry'). These complements often overlap in casual speech but carry distinct pragmatic weight. Advanced learners should pay attention to the subtle differences: 吃不了 (cannot finish), 吃不下 (too full to eat more), and 吃不起 (cannot afford to eat) all negate eating but for entirely different reasons.

Examples

1. 这么多菜我一个人根本吃不了。 There's no way I can finish all this food by myself.
2. 这个小会议室坐得下十个人吗？ Can this small meeting room fit ten people?
3. 以他现在的工资，在北京买不起房子。 With his current salary, he can't afford to buy a house in Beijing.

Usage Guide

Context: spoken, written, everyday

Tone: evaluative

Do Say

• 你一个人搬得了这张桌子吗？太重了吧。
• 这辆车最多坐得下五个人，再多就挤了。
• 她从小家里穷，上不起好学校。
• 别担心，这点困难我应付得了。

Don't Say

• 我吃不了得这碗饭。(得 and 不 cannot both appear — potential complements use either 得 for positive or 不 for negative, never together) → 我吃不了这碗饭。
• 这个教室坐不起二十个人。(起 expresses affordability or worthiness, not spatial capacity — use 坐不下 for fitting into a space) → 这个教室坐不下二十个人。
• 他买不了那栋别墅。(不了 implies inability to complete the purchase, not inability to afford — use 买不起 to express financial inability) → 他买不起那栋别墅。

Origin & History

Potential complements evolved from resultative verb compounds in Middle Chinese. The insertion of 得 or 不 between verb and complement to signal possibility emerged during the Tang-Song period, gradually replacing the earlier use of standalone modal verbs for expressing ability.

Cultural Context

Generation: All ages

Social background: Universal