问题补充：
Plants carbon dioxide and at the same time oxygen. So we may put some in our bedrooms to purify the air.
A. take in, give out
B. take up, give off
C. take over, give in
D. take off, give up
答案：
(答案→)A. take in, give out
B. take up, give off
C. take over, give in
D. take off, give up
解析：考察动词短语辨析。Take in吸收，理解，欺骗；take up占据，从事于，开始做；take over接管；take off起飞，成功，受欢迎；give out发出，分发；give off发出（烟，气味）；give in屈服；give up放弃；句意：植物在吸入二氧化碳的同时也释放出氧气，所以我们可以在卧室里放一些植物来净化空气。根据句意说明A正确。
