妈妈竖起手指放在嘴边发出“嘘嘘嘘”的声音提醒孩子们安静。

Mom put her finger to her lips and made a ___shush-shush-shush sound to remind the kids to keep quiet.

树叶在风中快速摆动，发出沙沙沙的声音。

The leaves made a ___shush-shush-shush sound as they rustled rapidly in the wind.