Scientistshavebeenstudying.Scientistshavebeenstudyingnaturalsourcesofmethanefordecadeshuthadn’tregardedplantsasaproducer.请说说句子成分?decadeshut

Question

Scientists have been studying .
Scientists have been studying natural sources of methane for decades hut hadn’t regarded plants as a producer.
请说说句子成分?decades hut

Answer 1

并列句复合句.
而且你单词肯定看错了,你把but 看成hut了
decades 跟but一点关系都没有.
前面句是,科学家研究沼气的来源已经有几十年了,但是（!）（他们）没有注意到植物也可以做生产者（生产沼气）.