越来越多的证据表明吸烟有害健康，这是使得吸烟率大幅降低最显著原因。

The most obvious reason for the sharp drop was the growing evidence of the harmful health effects of smoking.

youdao

越来越多的证据表明吸烟有害健康，这是使得吸烟率大幅降低最显著原因。

The most obvious reason for the sharp drop was the growing evidence of the harmful health effects of smoking.

youdao