题干

下列关于种群、群落、生态系统的叙述,错误的是( )

A:捕食者的存在有利于生态系统的稳定,外来物种入侵可能会破坏生态系统的稳定性

B:生态系统的结构包括生产者、消费者、分解者和非生物的物质和能量

C:某岛屿上植被茂盛,风景优美,该岛屿不同地段物种组成上的差异是群落水平结构的体现

D:标志重捕法调查种群密度时,若标志物部分脱落,则计算出的种群密度比实际值偏大

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B

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    If you're a high school student,you may tend to measure your self-worth based on your popularity and status.You may feel dejected or disappointed if you have a difficult time fitting in or if you lack the confidence to talk to others.If you want others to like you,you'll need to have a healthy understanding of how people think,what appeals to them and how you can gain their approval.There are four tips on how to be popular in high school.And if you are popular with your classmates,you can get many benefits from it.

    You must be yourself in order to gain any real popularity in high school.While imitation is the sincerest form of flattery(奉承),copying another's style and personality will have a negative effect on your popularity.If you're not comfortable enough to be yourself 100 percent of the time,others won't feel comfortable around you.If you establish your own style and finesse and stay true to yourself,popularity will soon follow.

    Make yourself approachable to appeal to others and be popular in high school.People love to be around others who are confident and ready to have a good time.Hold your head up high,keep your shoulders back,and smile as you walk with an air of confidence to instantly attract others and boost your popularity.

    Be friendly and kind to everyone you meet.It's not enough to gain the approval of the other popular students in your school.In order to gain real popularity,you'll need to be kind and polite to everyone you meet.Make an effort to talk to your classmates regardless of their popularity or economic status and try to develop friendships with them.The more people you appeal to,the more popular you'll become.

    Involve yourself in school activities that interest you.You can be popular in high school if you play an active role in your school's extracurricular activities(课外活动).The more you participate in group activities,the more popular you'll become.