`1.I have a habit of [listening ]to music while [studying ].
2.I am thirsty.Give me something [ to drink].为什么to drink 呢？give me something to drink. 给我些东西喝， 用动词不定式做宾语补足语为什么listening，studing呢？详细的说明行不行？of 介词后跟动名词， whlile studying = while I study