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- Mr. Smith gave a lesson on how to improve soil . 史密斯先生讲了一堂如何改良土壤的课。
- He gave a lesson on how to improve soil. 他讲了一堂如何改良土壤的课。
- He studied how to improve soil condition. 他研究如何改良土壤。
- He studied how to improve soil conditions. 他研究怎样改善土壤条件。
- Mr. Smith gave a lesson on how to improve soil. 史密斯先生讲了一堂如何改良土壤的课。
- Drugs can also artificially improve athletic performance,but it is cheating. 药品还可以使运动员以不正当手段提高运动成绩，但这是欺骗。
- An artificial waterway or artificially improved river used for travel, shipping, or irrigation. 运河,沟渠:人工水道或人工修缮的河流,用于旅行、航运或灌溉。
- It is showed that the sodication was the serious, the less aggregate of soil was, but that in improved soil increased obviously. 这说明土壤碱化程度越大，团粒结构越少；改良后土壤的团粒结构明显增加。
- The professor studied how to improve soil conditions. 这位教授研究如何改良土壤状况。
- A green manure is a crop grown mainly to improve soil fertility. 种植绿肥作物主要是为使土壤更加肥沃。
- Drugs in the sense of "dope" taken to artificially improve athletic performance. 兴奋剂可以使运动员以不正当于手段提高运动成绩。
- Wow. So this stuff could help feed people and improve soil. 哇，看来这种物质能够提高产量，还能改善土壤。
- A mixture of decaying organic matter, as from leaves and manure, used to improve soil structure and provide nutrients. 堆肥腐烂有机体的混合物，如树叶或粪便，用来改善土壤结构并增加土壤养分
- The improved soil aeration also accelerated the transportation of (superscript 14)C-photosynthates from leaves to root tubers, increased the ratio of root tuber dry weight to top dry weight. 促进(上标14)C同化物由叶片向块根的运转和分配，提高干物质在块根中的分配率；
- West Indian forage plant cultivated in southern United States as forage and to improve soil. 在美国南部栽培的一种西印度的饲料植物，也用于改善土壤质量。
- Soak of billabong broken bits makes straw fertilizer improved soil, improve wholesome ambient conditions, gained benefit of good economy, zoology, society. 沼渣沤制秸秆肥改良土壤,改善卫生环境条件,取得了良好的经济、生态、社会效益。
- Rational soil fertilization could improve soil nutrition and leaves nutritious level. 本实验的施肥试验表明，合理的土壤施肥可以提高土壤营养和叶片营养水平。
- The artificial improvement of drainage could soon lead to a marked loss in nutrients. 采用人工排水措施可以迅速导致养分含量显著降低。
- Mechanism and Measures for Improving Soil in Alkalisaline Land by use of Tamarix chinensis Lour. 利用柽柳改良盐碱地土壤的机制与措施初报。
- Robinia pseudoacacia is the best tree kind to improve soil of re-vegetation in the coal waste piles. 在同一植被恢复过的矸石山上刺槐林对土壤的改良作用最好。
