她边做作业边哼歌。

Tā biān zuò zuòyè biān hēng gē.

She hums while doing her homework.

哼着小调，她走进了屋子。

Hēngzhe xiǎodiào, tā zǒujìnle wūzi.

Humming a tune, she walked into the room.

他轻轻哼了一声表示同意。

Tā qīngqīng hēngle yī shēng biǎoshì tóngyì.

He hummed softly to indicate agreement.