孩子们在沙滩上收集各种颜色的蛤壳。

The children collected colorful ___clamshells on the sandy beach.

这家快餐店用塑料蛤壳盒装汉堡。

The fast food restaurant serves burgers in plastic ___clamshells.

工人们用蚌壳式挖斗清理河底的淤泥。

The workers used ___clamshells to dredge the silt from the riverbed.