就15秒，绕口令。
Betty Botter bought some butter but she said the butter's bitter。
If I put it in my batter it will make my batter bitter。
  
so, she bought some better butter,
better than the bitter butter。
she put it in her batter and her batter was not bitter。
  
so it was good that Betty Botter bought some better butter。

She sells sea-shells on the sea-shore。
  
And the shells she sells are sea-shells, I'm sure。
If she sells sea-shells on the sea-shore,
The shells she sells are sea-shore shells, I'm sure。
  
我在课本上给你找了俩适合15秒的，一个词一个词敲的。