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abstaining from smoking; quitting smoking
prohibition of smoking
No Smoking; Smoking Prohibited
健康のために禁烟を始めて半年になる。
It's been six months since I started quitting smoking for my health.
このレストランは全席禁烟になっている。
This restaurant is completely non-smoking.
禁烟に成功した友人が増えてきた。
More and more of my friends have successfully quit smoking.