Because they read it online .Because their bike has been broken for a while .Because they have really good hearing .None of the above choices .
What may be the reason why they learned to listen for a sound ?
I learned to listen for the sound the chain makes when it 's too loose . Eventually I felt confident enough to drive down to Oriental Bay to go for a ride . The homework was an hour to an hour and a half of hills . Under the circumstances I decided to ignore the hill part of the homework .