有点专牛角尖或者自己没看到， 问个prep07 119的一个小问题。。

zcstc007

题目不难，我有点专牛角尖的地方是， 答案中.the types of fossilized algae present in core samples 的  present不是应该用ING形式修饰algae的， 用动词原形是什么个意思这里？？不可能做谓语的啊

After determining the levels of calcium carbonate and the types of fossilized algae present in core samples taken from the bottom of Lake Titicaca in the Andes, a group of scientists was able to reconstruct the history of precipitation in tropical South America over the past 25,000 years.

A.the types of fossilized algae present in core samples taken from the bottom of Lake Titicaca in the Andes, a group of scientists was able

B.the types of fossilized algae that are present in core samples taken from the bottom of Lake Titicaca in the Andes, it was possible for a group of scientists
C.the types of fossilized algae that had been present in core samples taken from the bottom of Lake Titicaca in the Andes, that made it possible for a group of scientists
D.what types of fossilized algae had been present in core samples taken from the bottom of Lake Titicaca in the Andes, it was possible for a group of scientists
E.what the types of fossilized algae were that were present in core samples taken from the bottom of Lake Titicaca in the Andes, a group of scientists was able正确答案A

kiwifoodtown

LS正确，present第一词性是形容词，意义为目前，现在的。

wyw1018

present这里是形容词