The students lined up in response to the teacher's instructions.

He cleaned the bowl of the pipe thoroughly.

This cigarette contains carcinogens.

I used binoculars to observe birds in the mountains.

It is said that this substance has a high carcinogenicity.

He suddenly stiffened and fell down.

He was greatly excited about the new project.

This season, the cherry blossoms are blooming beautifully.

The efficacy of this medicine is very high.

He was enclosed in his own thoughts.