1、12岁的英语：12 years old，英 [jɪəz əʊld] 美 [jɪrz oʊld]。

2、儿童通常在11或12岁时升读中学。Children usually transfer to secondary school at 11 or 12。

3、那个12岁的男孩失踪三天了，警方对他的安全感到担忧。The police are concerned for the safety of the 12-year-old boy who has been missing for three days。