Teetotal is an adjective describing a person who never drinks alcohol at all — not 'drinks a little', not 'has stopped for now', but none, as a settled rule they live by. That completeness is the whole point of the word: you can say 'I don't really drink' and still have a beer at a wedding, but a teetotal person doesn't. You use it after 'be': 'She's teetotal', 'My grandfather was teetotal his whole life.' It sits before a noun much less often; 'a teetotal household' is possible but you would more often hear it about the person. The word is a bit old-fashioned and distinctly British in flavour — it comes out of the nineteenth-century temperance movement, where people signed pledges promising total abstinence, so there is a faint whiff of moral seriousness around it. Younger speakers today are more likely to say 'I don't drink' or 'sober'. Note that it says nothing about why: a teetotal person might be religious, might be a recovering alcoholic, might just hate the taste — the word covers all of them and asks no questions. The related noun for the person is 'teetotaller'.

滴酒不沾的（形容人完全不喝酒，通常是長期原則，不是暫時戒）。這個詞偏舊、偏英式；現在年輕人多半直接說 I don't drink。