填空题. A．Recently B．consumers C．chemicals D．environment E．combine F．transparent G．buy H．companion I．experts J．forms K．bury L．paper M．scholar N．plastic O．Usually A sunflower is a sunflower. A mobile phone is a mobile phone. But can you 21 the two to do something for your local 22 ? It may well be possible. When you have finished with your mobile phone you will be able to 23 it in the garden or a plant pot and wait for it to flower. 24 , a biodegradable mobile phone was introduced by scientists. It is hoped that the new type of phone will encourage 25 to recycle. Scientists have come up with a new material over the last five years. It looks like any other 26 and can be hard or soft, and able to change shape. Overtime it can also break down into the soil without giving out any toxic 27 . British researchers used the new material to develop a phone cover that contains a sunflower seed. When this new type of cover turns into waste, it 28 nitrates (硝酸盐). These feed the seed and help the flower grow. Engineers have designed a small 29 window to hold the seed. They have made sure it only grows when the phone is thrown away. "We've only put sunflower seeds into the covers so far. But we are working with plant 30 to find out which flowers would perform best. Maybe we could put roses in next time," said one scientist.