一…一…【yī … yī …】

一…一… puts 一 before each of two words to make a four-character phrase. Most of these are fixed, and the meaning depends on what kind of words are paired.

Paired nouns: every single

Two related nouns cover the whole of something, down to the smallest part.

一举一动 "every move" and 一点一滴 "every little bit" work the same way.

Opposite actions or directions

Two opposite verbs or direction words describe two people or two things doing complementary parts, or one action going back and forth.

Two contrasting things

Two opposite adjectives describe a pair that differ: one tall and one short, one big and one small.

Mistakes

These phrases are mostly fixed, so coining a new one rarely works. Measure words also stay out: 一 goes straight onto the word.

• × 一个高一个矮两个人 → 一高一矮两个人
• × 他的一句话一个行为 → 他的一言一行