一般来说,以辅音字母加O结尾的,加es;
例如:
embargo - embargoes,
hero - heroes,
torpedo - torpedoes,
veto - vetoes
而以元音字母加O结尾的,只加s;
portfolio - portfolios,
radio - radios,
ratio - ratios,
rodeo - rodeos,
studio - studios
但是,缩写单次除外,缩略词都是加S.比如,photo,它是photograph的缩写,就直接加s.