Derrick and I have been laying out the system of irrigating ditches.德里克跟我在一起修建那个灌溉网.He had been in command at the irrigating ditch the day before.上一天,在灌溉渠边,是他担任指挥的.The water in the irrigating ditch was well up.灌溉渠里涨满了水....
在用水以前先将其中不清洁的东西过滤掉.Filter out all the dirt before using the water.清洁的衣服和良好的举止能给人以好感.Clean clothes and good manners are prepossessing.和孩子讨论污染问题，强调清洁的街道、草地或公园有多么美丽。Discuss pollution with your child, emphasizing how nice a ...