Others viewed the findings with caution, noting that a cause-and-effect relationship between passive smoking and cancer remains to be shown.
Others viewed the findings with caution, noting that a cause-and-effect relationship between passive smoking and cancer remains to be shown.
因为注意到被动吸烟与癌症之间的因果关系还有待证明，其他人均以谨慎的态度看待这些发现。