阅读下面材料．在空白处填入适当的内容(1个单词)或括号内单词的正确形式．
Until recently, almost everyone thought that growth and progress would make the world a    (good) place. They believed that something new was always better than something old. So countries have spent billions of dollars       science to develop new ways of making things and doing work.      , this new technique is the main cause of the world’s problems. One such problem has come from the       (appear) of the car. In some       (crowd) cities, the car has polluted the air       badly that people get sick just from breathing it. Waste from factories is another example of how new technology is hurting the earth. When some waste chemicals    (put) into the sea, it can hurt or kill animals and fish. It’s time that we      (do) something quickly. When the problems get worse, they will not affect just a few     (country). They will be world problems      affect us all.