金属架子在重压下弯曲变形了。

The metal shelf ___buckled under the heavy weight.

面对持续的压力，她最终崩溃大哭起来。

Under constant pressure, she finally ___buckled and burst into tears.

她在发动汽车前扣好了安全带。

She ___buckled her seatbelt before starting the car.