Increased photosynthesis will use up carbon dioxide ; increased respiration produces more of it .
光合作用的增加会消耗二氧化碳，呼吸作用的增加则产生二氧化碳。
Last year buyers of china 's rare earths did not use up the available export quotas .
去年，中国稀土的买家并未用完既有的出口配额。
But I think fear is a natural asset - it helps me stay sharp and fighting it would only use up energy .
但是害怕也是正常的---他让我提高警惕，不断超越，倾尽全力。
Phytoplankton use up the nutrients available and growth falls off until winter storms kick-start mixing .
浮游植物耗尽了可用的养分后便停止了生长开始衰败，直到下一次冬季暴风再次搅动水体的混合。
The ability of some ecosystems to clean themselves up can also cause knock-on problems . When bacteria eat up oil-which they have been doing at the gulf 's oily seeps for millions of years-they use up oxygen too .
