问题详情:
It's necessary for human beings to breathe O2 and plants can ________ it.
A. develop B. produce C. improve D. introduce
【回答】
B
知识点:动词和动词短语
题型:选择题
问题详情:
It's necessary for human beings to breathe O2 and plants can ________ it.
A. develop B. produce C. improve D. introduce
【回答】
B
知识点:动词和动词短语
题型:选择题