Tongue Twister

[my life as erin (:]

Cool tongue twister... see if you can take up the challenge! Make sure you get every single word right! Read the following passage and then follow the instructions at the end. Read loudly, to yourself -
This is this cat
This is is cat
This is how cat
This is to cat
This is keep cat
This is a cat
This is fool cat
This is busy cat
This is for cat
This is forty cat
This is seconds cat

Now read the THIRD word in each line then you will understand what I mean!!!!!!!!