The numbers 0, 1, 2, 3, 4, 5, … (and so on) are whole numbers.
We use numbers to count things, like apples:-
1. 
Here's an apple. Just one apple.
2. Here's another apple. Now we have two apples.
One, two, three, four, five,
Once I caught a fish alive.
Six, seven, eight, nine, ten,
Then I let it go again.
One, two - buckle my shoe ,
three, four - knock on the door,
five, six - pick up sticks,
seven, eight - close the gate,
nine, ten - a big fat hen.
Ten green bottles
Hanging on the wall
Ten green bottles
Hanging on the wall
And if one green bottle
Should accidentally fall
There'll be nine green bottles
Hanging on the wall
And so it goes on...
Nine green bottles
Hanging on the wall
Nine green bottles
Hanging on the wall
And if one green bottle
Should accidentally fall
There'll be eight green bottles
Hanging on the wall
Eight green bottles
Hanging on the wall
Eight green bottles
Hanging on the wall
And if one green bottle
Should accidentally fall
There'll be seven green bottles
Hanging on the wall
Seven green bottles
Hanging on the wall
Seven green bottles
Hanging on the wall
And if one green bottle
Should accidentally fall
There'll be six green bottles
Hanging on the wall
Six green bottles
Hanging on the wall
Six green bottles
Hanging on the wall
And if one green bottle
Should accidentally fall
There'll be five green bottles
Hanging on the wall
Five green bottles
Hanging on the wall
Five green bottles
Hanging on the wall
And if one green bottle
Should accidentally fall
There'll be four green bottles
Hanging on the wall
Four green bottles
Hanging on the wall
Four green bottles
Hanging on the wall
And if one green bottle
Should accidentally fall
There'll be three green bottles
Hanging on the wall
Three green bottles
Hanging on the wall
Three green bottles
Hanging on the wall
And if one green bottle
Should accidentally fall
There'll be two green bottles
Hanging on the wall
Two green bottles
Hanging on the wall
Two green bottles
Hanging on the wall
And if one green bottle
Should accidentally fall
There'll be one green bottle
Hanging on the wall
One green bottle
Hanging on the wall
One green bottle
Hanging on the wall
If that one green bottle
Should accidentally fall
There'll be no green bottles
Hanging on the wall
You can try a shorter version with sticks of dynamite:-
Ten sticks of dynamite
Hanging on the wall
Ten sticks of dynamite
Hanging on the wall
And if one stick of dynamite
Should accidentally fall
There'll be no sticks of dynamite
And no bloody wall.
