嫂嫂怎么说？是“sister in law”，还是“brother's wife"?

正确应该是：
嫂嫂: sister-in-law,
哥哥／弟弟的老婆: brother's wife.

当我介绍嫂嫂时会说: she's my sister-in-law, my elder brother's wife.

同理：
妹／姐夫: brother-in-law,
妹妹老公：younger sister's husband,
姐姐老公：elder sister's husband.

SISTER-IN-LAW

sister in law

sister-in-law

sister in law

sister in law