史前哺乳動物的身體結構: hair,fur,tooth,head,jaw,horn,armor,antler, pouch 史前哺乳動物的行為動作: feed,hide,fight,eat,crush,hunt,escape 史前哺乳動物的外貌特征: small,tiny, huge,large,long,saber-liketooth, strong, giant, fierce, sharp tooth, heavy, furry 與史前哺乳動物的生活習性有關的詞: earth,land,milk,meat-eatingplant-eating, ocean, ice age give birth to sb./sth.生孩子，產仔 die out 滅絕 millionsof數百萬的 be full of...充滿...... not...anymore 不再...... with 復合結構作原因狀語: But with all the big dinosaurs gone,mammals didn't have to hide anymore. 時間狀語從句: Fish swam away fast when this huge hunter wasnearby. 定語從句: The hornless rhino was the biggest mammal that hasever lived on land. 比較狀語從句: Giant kangaroos were much bigger than today'skangaroos. 定語從句: Manatees are mammals that live in the water. 比較狀語從句: That's as long as two kids'bikes lined up endtoend. 被動語態:Amanatee baby is called a calf 動名詞短語作主語: Swallowing trash can hurt manatees 結果狀語從句: Fishing line can get tangled around manatees sothey can't swim.