Imaginary Play structure

I went to the park when it was so hot.

Then I got thirsty.

I slid down a fat pole,

Which was only a birch tree.

When I was tired,

I went down the slide.

But I tell you,

It wasn't my greatest pride.

When I felt like sitting,

I went to the swing.

But it was funny,

I went through that thing.

Are these things real?

Am I having fun?

Oh! now I see,

It's just an illusion!