nǐ yào yì bēi shuǐ ma?

you

Breakdown of nǐ yào yì bēi shuǐ ma?

• 吗ma: question particle
• 水shuǐ: water
• 要yào: to want

Questions & Answers about nǐ yào yì bēi shuǐ ma?

Why is 一 pronounced yì here instead of yī?

Tone sandhi. 一 (yī) changes its tone depending on what follows:

• Before a 1st, 2nd, or 3rd tone, it becomes yì: 一杯 (yì bēi), 一年 (yì nián), 一碗 (yì wǎn).
• Before a 4th tone, it becomes yí: 一个 (yí ge), 一份 (yí fèn).
• When counting numbers in isolation, it’s yī.

Why do we need 杯? Why not just say 一水?

Chinese needs a measure word (classifier) between numbers and nouns. The pattern is Number + Measure + Noun. For liquids you usually use a container as the measure:

• 一杯水 (yì bēi shuǐ) a cup/glass of water
• Compare: 两瓶水 (liǎng píng shuǐ) two bottles of water, 一碗汤 (yì wǎn tāng) a bowl of soup

What’s the difference between 杯 and 杯子?

• 杯 is a measure word meaning “cupful/glass.”
• 杯子 is the actual physical cup. Examples:
• 给我一杯水。 Give me a cup of water. (measure)
• 我有一个杯子。 I have a cup. (object) You may hear 一杯子水, which colloquially emphasizes “a whole cup of water,” but the standard way is 一杯水.