Friends of the Earth help keep the environment clean.对“ keep

What do friends of the Earch help?
Friends of the Earth 是主语：地球的朋友；谓语动词是 help
"keep the environment clean"是宾语,对宾语的提问
谓语动词是行为动词时,必须在句首加上助动词Do、Does（三单）、Did（过去式）加上这些助动词后,句子中谓语动词必须用原形.
eg.1)Edison built a science lab himself when he was ten.（改成疑问句）
______ Edison ______ a science lab himself when he was ten?
2)Those Japanese like Chinese food.（改成疑问句）
______ those Japanese ________ Chinese food?

Earth is our mother, nuturing our growth. however, she is suffering now due to selfishness of some people. Global warming, ice cape melting, rising sea level and deforestation are reasons driving the ...

What do the friends of the Earth help