Can you find the missing piece of the Porsche?

Can you spot what's wrong with the following sentence?

PETER WAS ANGRY AT
HIMSELF BECAUSE HE
ACCIDENTALLY LEFT THE
THE KEYS TO HIS CAR
AT HIS FRIEND'S HOUSE.

Give it food and it will live; give it water and it will die.

The Puzzle: A girl, a boy, and a dog start walking down a road.

They start at the same time, from the same point, in the same direction.

The boy walks at 5 km/h, the girl at 6 km/h.

The dog runs from boy to girl and back again with a constant speed of 10 km/h. The dog does not slow down on the turn.
How far does the dog travel in 1 hour?

You knock a Table over in the library, and suddenly 20 eyes are looking at you.

What is the riddle which can be asked all day with a different correct answer each time.

I have a big mouth and I am also quite loud! I am NOT a gossip but I do get involved with everyone's dirty business.

You may enter, but you may not come in. I have space, but no room. I have keys, but open no lock. What am I?

I came first on earth but second on the heaven.
I also came twice in a week but found just once in a year.
I stay away from months but you can find me in February.

What am I?

I know there are two methods by using three time the same number with a plus(+) operator , you can make sum as 60.

One of them is 20+20+20.

whats the other way ?