That smoking causes lung cancer is well established.

吸烟会引发肺癌已经毋庸置疑。

youdao

The evidence that smoking causes lung cancer is very compelling.

吸烟会导致肺癌的证据很有说服力。

youdao

There is now convincing evidence that smoking causes lung cancer.

现在我们有足够的证据证明吸烟会引起肺癌。

youdao

The World Health Organization says at least five million tobacco users die every year from lung cancer, heart disease and other smoking-related causes.

VOA: standard.2010.02.18

Smoking causes lung cancer, at least a dozen other cancers, as well as cardiovascular disease and lung disease.

CNN: Is secondhand smoke really that risky?