托福机经作文
1 综合
托福机经阅读：考古大发现啊~~恐龙骨头里面发现了很多东西，证明来自于血管，血细胞，骨髓。
1 有breaking channel像血管，soft物质遗留物
2sphere with iron是红细胞的，
3collagen是骨髓里面的重要物质
Listening:
Lecturer认为托福机经阅读中的证据Skeptical。
(1) The material found in the breaking of the bone can not prove the existence of red blood vessel. It is more likely to be other material such as the reddish mineral.
(2) Sphere also appears in other animals that do not have bone tissues. For example, it may be the traces left by the bacteria colony that lived in the bone leg after the dinosaur died.
(3) Collagen can not remain as long as a period of 70 million years. So it is more that the collagen comes from other recent sources such as the human skin of some researcher who handled this bone leg before.