Horses , lions and dogs are quadrupeds , but humans are bipeds .

马、狮子和狗是四足动物，但人是二足动物。

Some quadrupeds are not housesbecomes , by contraposition , some thing not house are quadrupeds .

某些四足动物不是马，以反言论法，变成了某些不是马的东西是四足动物。

The joint of the hind leg analogous to the human knee in certain quadrupeds , such as the horse .

后腿膝关节：某些四足动物后腿象人的膝盖一样的关节，如马。

" Some quadrupeds are not houses " becomes , by contraposition , " some thing not house are quadrupeds . "

“某些四足动物不是马”，以反言论法，变成了“某些不是马的东西是四足动物”。

Maybe her language is a bit clinical : there 's a chapter on how to cook " quadrupeds " .

也许她用的语言稍微有点生僻：比如，有一章是讲如何烹饪“四足动物”。