她用夹子把晾衣绳固定在栏杆上。

She used ___clamps to secure the clothesline to the railing.

他用夹具把两块木板夹紧固定。

He ___clamped the two wooden boards together to secure them.

学校在考试期间严格限制手机使用。

The school ___cracked down on mobile phone use during exams.