balloon和football的读音不一样:
/u:/，/u/
The balloon carried two large parachutes .
气球携带着两个大型降落伞。
The balloons will start popping any minute now .
气球马上就要爆了。
The colourful balloons rose high into the air ..
五颜六色的气球腾空而起。
They like to go ballooning at weekends .
他们周末喜欢乘气球玩。
Most big balloons are now filled with helium .
现在许多大气球中充的是氦气。
