Mammals breathe with ____.

A. lungs
B. gills(鳃）
C. wings
D. eggs

The process that takes place as a tadpole (蝌蚪) changes into a frog is ____.

A. digestion (消化）
B. metamorphosis (变形)
C. photosynthesis (光合作用)
D. protection

____ is the only mammal capable of true flight.

A. The bald eagle
B. The flying squirrel
C. The bat
D. The penguin

Chickens eat food using their_____

A. beaks
B. mouth
C.teeth
D. claws

Elephants are often killed because hunters want to sell their_______

A. horns
B. tusks
C. feet
D. tails

Geese, ducks and other birds are covered in_____

A. fur
B. feathers
C. hair
D. spikes

将下列字母重新组合成一个动物单词。hawle

veebar

noil

pheleatn