阅读下面短文，按照句子结构的语法性和上下文连贯的要求，在空格处填入一个适当的词或使用括号中词语的正确形式填空。
Cars will run on solar power (太阳能) or electricity and will be much cleaner. They will be much (safe). For example, if you are too close to another car or if you are driving (danger), your car will slow downitself.
Because there won't be any spare land, new cities will have to be built in the sea. Some (city) on water will have two levels. People will live on the upper level,the lower level will be used for traffic, shops and factories.
Biotechnology (生物技术) will make food better and healthier. Plants that are not affected by insects or (illness) will be developed. The taste of fruit and vegetables will be (good) and food will be kept longer.
New technology will be used (make) TVs that are only 1cm thick. They will have pictures that are as clear as photos. Electrical appliances (电器) will be quieter and will be controlled by computers. They will also use 50% power.
Using products of genetic engineering (基因工程产品), many new ways to cure (治愈) illnesses will be (success) . Cures will be found for the flu and the common cold. However, some new illnesses will appear.