题干

为了探究植物呼吸强度的变化规律,研究者在遮光状态下,测得了相同的新鲜菠菜叶在不同温度和O2含量条件下的CO2释放量,结果如下表(表中数据为相对值)。下列有关分析,错误的是(   )

A:根据变化规律,表中10℃、1.0%条件下的数据很可能是错误的

B:温度为3℃、O2含量为3.0%是贮藏菠菜叶的最佳环境条件组合

C:O2含量从20.0%升至40.0%时,O2含量限制了呼吸强度的继续升高

D:在20℃条件下,O2含量从0.1%升高到3.0%的过程中,细胞无氧呼吸逐渐减弱

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C

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How to write an email?

    While many people are accessible by email, sometimes it is difficult to determine how exactly to write an email to them. Here are some tips for you to follow.

Write an appropriate subject line. The subject line should tell the recipient (接收者) immediately what the email is about. ____Remember that your wording also has to be brief.

    ____ It is best to be more formal rather than informal, so when writing to someone you have never met or written to before, a “Dear Jane Smith” is appropriate. When addressing someone whom you are a little familiar with, a “Dr. Smith” is okay until they tell you to address them by their first name, in which case a simple “Jane” will be okay.

    ____ Within the first two sentences of your email, your recipient should know exactly why you are writing to him. Sometimes an introduction may have to precede (先于) the sentence that states why you are writing, and sometimes it has to follow.

    Use appropriate language. You may be used to using informal language in certain social settings. ____Even when dealing with colleagues or friends you are familiar with, do not immediately fall back on informal language.

    Keep it simple. People may get dozens and even hundreds of emails a day.____In that way, they can save much of their time when reading emails.

A. Use proper greetings.

B. Express your ideas clearly.

C. State your purpose at the beginning.

D. Be as specific as possible when writing the subject.

E. However, an email may not be the best place to use such language.

F. It is important to check the language to avoid spelling and grammar mistakes.

G. It is always easier for them if you keep your email as short and brief as possible.