题干

下列有关群落演替的叙述中,错误的是

A:人类活动往往会使群落演替按照与自然演替相同的方向、速度进行

B:在群落演替过程中,不同时期群落中的优势种群在发生更替

C:发生在裸岩上的演替经过:裸岩→地衣→苔藓→草本→灌木→森林五个阶段

D:群落演替主要有初生演替和次生演替两种类型

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A

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    Last winter vacation, my brother got a set of bedroom furniture for his thirteenth birthday. When it arrived, I helped my parents moved the 1  furniture to the garage(车库). It was still in good condition. I thought it might be a chance for us to2 someone in our community. I started to search neighbors, anyone who 3 a bedroom set. Finally, my mom helped me call the local primary school. They told me about Jaila, the daughter of a poor single mother. I was given a telephone number and 4 and I soon found myself at Jaila's.

    The moment I went into Jaila's room, I knew I had taken on too big a task. When I pushed the old door open, it made a long high noise. But the door was nothing compared with the rest of the room. Some old paint was 5 the wall. One of the windows was 6. The bed was just a mattress(床垫)on the old carpet. It seemed that the room needed7 furniture — it cried — for a complete makeover(翻新).

    That day I spent at least an hour looking around and 8how I could possibly fixed the room. I had never painted a wall, let alone fixed a floor. The second day, I returned with a large group of helpers — my close friends. We went to collect everything needed door to door in our community. We replaced and repainted Jaila's room. We sweated in Jaila's house for more than ten hours every day that week.

    The moment we finished, we called Jaila into the room. She jumped, laughed and hugged each of us. I turned to Jaila's mother, and saw she had tears running down her face.

    "Anna," Jaila called my name 9Yes?""Welcome to my new room!"

    When we saw how happy Jaila and her mother were, our tiredness disappeared into thin air. We are really10 to make a special experience of changing someone's life.