byproduct|byproducts

睡眠不足是过度工作的一个副产品。

Lack of sleep is a ___byproduct of working too much.

造纸过程中会产生木屑作为副产品。

Wood chips are ___byproducts of the paper-making process.

在造纸过程中，木质素是一种有用的副产品。

Lignin is a useful ___byproduct in the paper-making process.