美国是世界上的农业大国，农业生产效率高，成本低，产品市场竞争力强。这种特点形成的主要原因是（ ）。
①气候条件优越
②耕地广阔，土壤肥沃
③高度机械化和区域生产专业化
④农业科技发达
A．①②
B．①③
C．②③
D．③④

能体现本文主旨的词语是( )（l分）A．明察秋毫 B.物外之趣 C．怡然称快 点击查看答案

Many people think of plagiarism as copying another’s work，or borrowing someone else’s original ideas.As a matter of fact，plagiarism involves both stealing someone else’s work and lying about it afterward.So plagiarism is an act of fraud，then what can be done to change the situation？Write a composition of about 200words on the following topic：How to Prevent Plagiarism You are to write in three parts.In the first part，state what your suggested ways are.In the second part，support your suggestions with appropriate details.In the last part，bring what you have written to a natural conclusion or a summary. 点击查看答案