夜间不宜将盆载植物放在密闭的卧室内，主要是因为植物的呼吸作用
A．吸收二氧化碳放出氧气
B．净化空气
C．吸收氧气放出二氧化碳
D．降低室温
答案：C
题目分析：在晚上卧室植物因为没有光所以不能进行光合作用，不能释放氧气，但是植物在晚上能进行呼吸作用，因而会吸收卧室内氧气，由于卧室密闭，空气中的氧气不能进入，会造成人与植物争夺氧气，造成氧气减少二氧化碳增多，对人类健康不利。
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| My name is Wang Kun and my sister is Wang Wei. Since middle school, we have dreamed about taking agreat trip by 1 . When we graduated from college,we finally got the 2 to do it. We started our long bike ride 3 the Mekong River (循公河) in October. 4 it was autumn, thesnow had already started to fall in Tibet. Our legs felt so heavy and 5 that we thought they were ice. Have you ever seen 6 ride bicycles? Wang Wei was in front of me as usual. I knew I didn't need toencourage 7 . To climb up the mountain road was hard work but to go 8 the hills was great fun. When we reached a valley (山谷), it became much warmer. We had to 9 our clothes. In the early evening, we stopped to 10 our tents and then we ate. After supper, Wang Wei went to 11 but I stayed awake. At midnight, the sky became clear and the stars were 12 . There was almost no 13 only the sound of the fire. What a 14 night! We have already traveled so far. We are reaching Dali in Yunnan Province. There our cousins Dao Wei and Yu Hang will 15 us in the ride trip. I'm sure we'll have a greater time together. | ||||
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