The drugs tend to cause drowsiness.

这些药常常使人昏昏欲睡。

Big meals during the day cause drowsiness.

白天的大餐会让人犯困。

A heavy drowsiness presently fell upon the two comrades.

不久，两个同志打起了瞌睡。

How the? I said microstrip drowsiness.

怎么了？我微带睡意的说。

Vapours may cause drowsiness and dizziness.

蒸汽可能引起困倦和眩晕。