一、表示人的物主代詞用my， our， your， his， her和their，指無(wú)生命的東西用its(但指國(guó)家時(shí)一般用she或her)，它們?cè)诰渲凶鞫ㄕZ(yǔ)

　　二、名詞型物主代詞能作表語(yǔ)(It’s theirs)、主語(yǔ)(Mine is there)、賓語(yǔ)(I don’t like hers)，與of連用可以作定語(yǔ)(the food of theirs)。

　　三、同步練習(xí)

　　1) A scientist bases its [A] work on hypotheses that [B] have been checked [C] through careful [D] experimentation.

　　2) Crude rubber is an [A] elastic(有彈性的) solid with a specific gravity of 0.911 and a refractive index(折射率) of 1.591， though it [B] composition varies with different latexes(橡漿) as well as [C] with the way it is prepared [D] at the plantation.

　　3) Manufacturers [A] of consumer goods [B] often change [C] the styles of them [D] products.

　　四、例題解析

　　1) A錯(cuò)。 改為his.

　　2) B錯(cuò)。 改為its.

　　3) D錯(cuò)。 改為their.