帮我分析一下这个英语句子的结构~
The marine environ-ment,representing more than two thirds of our planet,is still under-explored and
is considered to be a prolific resource for the isolation of less exploited microor-ganisms and to produce new antifungal substances.
这个句子中的representing more than two thirds of our planet是什么成分?整个句子是什么从句?楼主大学毕业7年多了,语法都忘了,今天看英文文献,意思能懂,语法完全不行,过一阵要写英文文献,全都重检起来真痛苦!