You shouldn't use your cell phone in class.
Sypha is in class trying to study and then her phone vibrates.
Sypha wants to finish studying.
Sypha lets the phone vibrate, so they can leave a message she'll check later.
Sypha answers the phone and talks on it while she's studying.
The classroom stays quiet and everyone can study calmly for the period.
Everyone around her is bothered by her talking while they are trying to study.