酸化: oxidize, become oxidized / 参加: participate, join, take part

A title used after person's name (first name or surname) regardless of sex; Mr, Ms, Mrs, Miss. Also used after a job title and a company name. / (colloquial) Used after a shop name.

三人: three people

三角形: triangle

三月, 3月: March

賛意: assent / 三位: third rank / 三尉: second lieutenant

determine, fix, establish, decide

(politics, historical) the minister of the left, the second-highest government position in the 太政官 (Daijō-kan, “Great Council of State”, the highest government office under the 律令 (Ritsuryō) system)

a male given name

usual, regular / stereotyped