To grab something is to get it or reach for it very quickly. People grab things with their hands:
simple
past
past participle
grab
grabbed
grabbed
We grabbed some food from McDonald’s before leaving on our trip.
Tim grabbed a few apples before walking out the door.
If you happen to see Louise, grab her for me because I need to talk to her.
During a football game, players try to grab the ball away from their opponents.
Don’t forget to grab your coat before we leave.
Grab your hat and an umbrella. It’s raining outside.
That TV commercial really grabs your attention.
Sometimes we use the word "grab" to describe an assault of some kind:
A mugger grabbed Lisa from behind and stole her purse.
A mob of screaming girls tried to grab onto the young teen idol as he passed by them.
A police officer grabbed the suspect and threw him to the ground.
A dog grabbed the leg of a man who was threatening the dog’s owner.
The police officer grabbed the man by his coat and told him to stop what he was doing.
There’s a common expression that uses the word "grab." To say that something is up for grabs means that it’s available to the first person who claims it or picks it up.
The Johnson’s say that in their backyard they have a play set that’s up for grabs to anyone who can take it apart and haul it away.
The school has some old desks that are up for grabs, but you’ll have to act quickly because the desks are pretty nice.
I’ve got an old phone that’s up for grabs. Who wants it?