Young people are often unhappy when they are with their parents. They say that their parents don’t understand them. They often think their parents are too strict1them.
   Parents often find2difficult to win their children’s trust and they seem to3how they themselves felt when they were young.
For example, young people like to do things without much4. It’s one of their ways to show that they grow up and they can5any difficult problems. Older people worry more easily. Most of them plan things ahead and don’t like their plans to be changed. So when you want your parents to let you do6, you will have better success if you ask  before you really start doing it.
   Young people often make their parents angry by clothes they wear, the music they enjoy and something7. But they don’t mean to cause any trouble. They just feel that8this way they can be cut off from the old people’s world and they want to make a new culture of their own. And if their parents don’t like their music or clothes or their way of speech, the young people feel very sad. Sometimes instead of going out with their parents, they just want to stay at home9and do what they like.
   If you plan to do something, you’d better win your parents over and get them to understand you.10, your parents will certainly let you do what you want to do.

    According to a Chinese saying, he who doesn't reach the Great Wall of China is never a great man.

    Growing up in Beijing I1 its historical sites and natural attractions perfectly well. However, I'd 2 climbed the Great Wall before until recently. I, along with my friends3for the top. We soon discovered that the hike was much more 4 than we had imagined. But we didn't 5.It took us about two hours to finally6 where we had wanted to get to.

    As I 7 at the top of the Great Wall, I looked back at the waves of8 walking to the top. At that moment, I saw an amazing 9 that would forever change my opinion on humans' limits. I saw young couples carrying their children, walking10 but surely towards the top. They would stop once in a while to take a11 under the hot sun.

    As I stood there, I began to 12 words that can describe us humans. If one would like to describe Giraffes (长颈鹿), he/she would use words such as 13 and long-necked -But what about us? I took another look down below and my 14began to gather, persevering (坚持不懈的), determined, and 15As these words came into my mind, I 16 that it was not appearance or physical characteristics that should define (定义) us humans, but the 17 that we share.

    I don't know if I became a 18 man after returning from this 19 according to the Chinese saying20 I surely returned as a more thoughtful person.

在同一平面内，两条直线的位置关系是（　　）

下列对非生物因素的描述中错误的是（  ）

已知$△ABC$,点H,O为$△ABC$所在平面内的点，且$\overrightarrow{AH}·\overrightarrow{AB}=\overrightarrow{AH}·\overrightarrow{AC},\overrightarrow{BH}·\overrightarrow{BA}=\overrightarrow{BH}·\overrightarrow{BC},\overrightarrow{OA}+\overrightarrow{OB}+\overrightarrow{OC}=\overrightarrow{OH}$, 则点O为$△ABC$的 (  )