Because Rudolph intentionally grounded the team...
Better question would be: Why were they in the tree in the first place?
They held the telephone wires off the ground.
King's Landing
Grounds for termination.
The Ground
They throw silverware on the ground!
Littering.
Ground and federal expresso
The ground!
Because he was grounded.
Because it's grounded.
In the ground.
Noone cares.
Because it was s knotty pine!
Well, well, well
Grounding
1 Terrahertz
You would too if you had to fly Alitalia.
Because he was grounded!
Because he reached terminal velocity.
They're grounded.
His grades were below sea level
Under the ground.
You're grounded.
He felt the slack in his dog's leash.
It's your fault!
The beans are always under-ground.
Well, well, well My grandpa's favorite joke. Took me five years to get it.
An eggplant.
Because you can't bury them in trees!
None
The rest of your life.
Hippocampus!
Your career
Grounds for termination!
Barium.
Because it was two-tired
Stay grounded.
The leash goes slack.
When they're astronauty.
Because you can't bury them in the sky!
Because they were under-ground.
It didn't have any pickups
Because they'll worship the ground you walk on.
She was trying to find the lowest prices
Because that would be "grounds" for termination!
Sinkhole de Mayo
A dead centipede.
A fruit by the foot
Because it was grounded.
When it falls to the ground, it knocks the 'ell out of it.
That's grounds for divorce!
One, but you can be sure a whole Reddit community will appear to expand the joke, make it funnier and eventually run it into the ground.
The ground.
Noone. Pirates don't have poles, they have masts.
Running into one could really ruin your day.
This place feels earie.
Two. One to hold it in place, another to rotate the universe around it.
Just one. He holds up the bulb and waits for the world to revolve around him.
None. They'll just stand in the dark talking about how good the old one was.
It's CoRnY
Dalek themselves clean
Hold On, Not Done Accelerating.
A saucer-er!
People who give 110%
Because 111 1000 1001
Get off me, homes.
A hole-y Cow!