Listen to the passage and complete the table 根據(jù)你所聽(tīng)到的內(nèi)容，完成下列句子。每空格限填一詞。
（1）In the future，it will be easier to find ____ for parking cars if people drive small cars.
（2）Small cars can go only ____ kilograms per hour，so driving will be safer.
（3）These small cars will cause less____ in the air.
（4）In the world under the water，there will be no____.
（5）People can ____ some beautiful fish as their pets.
（6）People can use the machine to ____ the air in the water into fresh air.