adulterate|adulterated|adulterating

一些商家会在牛奶中掺水来降低成本。

Some merchants ___adulterate milk with water to reduce costs.

这瓶蜂蜜被掺了糖浆，品质大打折扣。

The honey was ___adulterated with syrup, reducing its quality.

黑心商人通过掺水来伪造蜂蜜。

Unscrupulous merchants are ___adulterating honey by adding water.