Q28:
Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated at 34 million years old, made it the earliest known mammal of the Greater Antilles islands.
- sloth found in Puerto Rico in 1991, and dated at 34 million years old, made it the earliest known mammal of
- sloth, that they found in Puerto Rico in 1991, has been dated at 34 million years old, thus making it the earliest mammal known on
- sloth that was found in Puerto Rico in 1991, was dated at 34 million years old, making this the earliest known mammal of
- sloth, found in Puerto Rico in 1991, have been dated at 34 million years old, making the sloth the earliest known mammal on
- sloth which, found in Puerto Rico in 1991, was dated at 34 million years old, made the sloth the earliest known mammal of
这题在讨论贴里大多数人都选D，对于D，found in Puerto Rico in1991,如果做定语的是不是省略了which be，可是这样的话，它不是应该修饰sloth了麽（因为which 是直接修饰它前面的名词的啊）？