题干

下列关于绿色开花植物开花和结果的叙述,错误的是(  )

A:雌蕊和雄蕊是花的主要结构

B:传粉和受精是种子形成的前提

C:果实是由子房发育而成的

D:种子是由受精卵发育而成的

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答案(点此获取答案解析)

D

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How to become a better runner

  This is meant for runners in high school .If you want to become a better runner, then here are several things you can do.

  Connect with your team if you are new. ____ .You can ask them for advice and hang out with them outside of practice!

  If you have a workout,don’t slack off(松懈) ever.This will never improve your performance .

____ .I know some people say they do it just to stay in shape,but if you want to stay in shape you have to work for it!

  Run 6 out of  the 7 days in a week, but don’t work out on your days off. You need to relax.

____ .It dosn’t have to be as much as you would run during practice, but you should still exercise so that you don’t get out of shape.

  If you are injured, do not run. ____ . It’s common to get shin splints(小腿酸痛), so if this happens to you ,just take a break from running. It will actually make you better once you start running.

    ____ .It allow you to form a relationship with other people like a family. If you take time to become a better runner, you will be physicaaly and mentally(精神上地) stronger.


A, It takes much of your time.

B,Running is more than a sport.

C,Running can make problems worse.

D,It is an experience that you will never forget.

E,But if you are having a long break , you should still run.

F,Remember that you are supposed to run in a running sport.

G,It helps you realize that there is more to just the sport to look forward to.