吗 (ma) — (question particle) used to form yes-no questions

A sentence-final particle that turns a statement into a yes/no question: 你喜欢苹果 → 你喜欢苹果吗？ (Do you like apples?). It does not need a question word and the sentence still has normal statement word order.

Most characters — around four in five — are built this way: one part hints at the meaning, the other at the pronunciation.

This origin belongs to the traditional form 嗎; 吗 is its simplified writing.

The traditional form 嗎 pairs 口 (mouth) with 馬, which gives the sound. The simplified 吗 is a later shorthand, so its right side is not the historical 馬.