Q: My MacBook air shuts down and will not completely open what shou I do

Hi Sheila,
 

Thanks for participating in the Apple Support Communities.
 

If your MacBook Air doesn't start up to the desktop, you can Try safe mode if your Mac doesn't finish starting up. If you don't hear the startup chime or see the Apple logo, try the troubleshooting steps in If your Mac won't turn on.
 

All the best.