来源：沪江听写酷 2013-04-08 04:00
450)this.width=450"> [color=#600000]BEC HIGHER 听力训练，希望对备考的同学们有所帮助。 全文听写，英式拼法[/color] 商务英语播客每日19点更新，BEC高级每日9点更新。 450)this.width=450"> 上一期BEC高级：产品演讲(1/3) HINTS none
Because he was on holiday for two weeks and had no-one in the block of apartments that he felt he could ask to look after his plants, he devised a simple automatic watering system. Basically, it consists of a container of water, a valve and a humidity sensor. When the humidity sensor detects that the earth in the plant pot is too dry, it causes a valve to open and release a fixed amount of water from the container into the plant pot. As long as the earth is damp, the valve remains closed. We also have in the pipeline a more sophisticated model which can be used all the time, not just when you are away from home. With a range of settings, it allows you to set Plant-carer to deliver exactly the amount of water indicated in the plant care instructions, watering them as they need to be watered. The result is that the average person can care for a plant as an expert would.