他用围巾捂住嘴巴来减小说话声。

He ___muffles his voice with a scarf when he speaks.

她戴上耳罩来减轻吵闹的音乐声。

She wore ear covers to ___muffle the loud music.

她用手捂住嘴，试图压抑自己的尖叫声。

She covered her mouth with her hands to ___muffle her scream.