therefore many people think that smoking is legal that is a
3个回答

Therefore many people think that smoking is legal,that is a direct and primary reason to induce this kind of problem.

这个句子里缺少一个逗号或句号,在legal后面.

第一个that是宾语从句的引导词,无含义;

第二个that作为后面一个句子的主语,指代的是前句里说到的问题.

因此,很多人认为吸烟是合法的,那就是导致这个问题的直接和根本原因.