一、這是A及B各人的房子。
This is A's and B's house.
Ans：這是個別所有格，所以應該為複數故應為 These are A's and B's houses.

二、他有四頭狗；一頭是黑色的，剩下其他的皆是白色的。（指其他三頭）
He has four dogs; one is black and the others is white.
Ans：the others 應為複數，所以應為 He has four dogs; one is black and the others are white.

三、他有十頭狗；一頭是黑色的，別的狗是白色的。（指其他部分的狗）
He has ten dogs; one is black and others is white.
Ans：同二，He has ten dogs; one is black and the others are white.

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