1、詞性上的區(qū)別their是形容詞物主代詞，后面可以接名詞。

theirs是名詞性物主代詞，后面不能接名詞2、意思上的區(qū)別their：他（她，它）們的theirs：他們的; 他的或她的。造句：

①、theirIt would cost about ￡ 3,000 to install a new heating system in a flat such as theirs在他們那樣的一套公寓房里安裝一套新的供暖系統(tǒng)可能要花費3,000英鎊左右。Theirs had been a happy and satisfactory marriage. 他們的婚姻曾經(jīng)一直幸福美滿。

②、theirsThere was a big group of a dozen people at the table next to theirs 他們旁邊的桌上坐了一大群人，有十幾個。This child is nobody's child until someone makes her theirs officially. 在有人辦理正式手續(xù)認(rèn)領(lǐng)以前，這個孩子不屬于任何人。擴展資料theypron.她們；他/她/它們；人們，大家;政府，當(dāng)局。例句：They say there's plenty of opportunities out there, you just have to look carefully and you'll find them 他們說，那里機會多的是，你只要仔細(xì)找就能發(fā)現(xiàn)。People matter because of what they are, not what they have 人之所以重要，不在于他們擁有什么，而在于他們是什么樣的人。The young horses broke in a pack, and over the first furlong, they remained in a pack. 幾匹小馬一起沖出，跑完頭一弗隆后還沒拉開距離。