她把脏水倒进了下水道。

She poured the dirty water down the ___drain.

市政工人正在清理堵塞下水道的落叶。

The council workers are clearing the blocked ___drain of fallen leaves.

水槽下的排水管堵住了，我需要叫水管工来疏通。

The ___drain under the kitchen sink is blocked, so I need to call a plumber.