Time and again,however,such studies encounter the same objection: are the problems caused by smoking marijuana,or is it just that people with problems are more likely to end up using marijuana heavily?
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- 但是每一次这些研究都碰到了同样的反对意见:这些问题是因为吸食大麻而起,还是有这些问题的人最后更有可能大剂量吸食大麻?