Oh s**t, I forgot my keys!

I stepped on a piece of s**t on the sidewalk.

He accidentally stepped on s**t while walking in the park.

Bulls**t! I can't believe you lied to me.

I can't stand all this bulls**t.

I can't believe he's bullshitting us again.

Oh sh*t, I forgot my keys!

I stepped on a pile of sh*t on the sidewalk.

I can't believe he sh*t on the floor!

The reaction involves the addition of t-butyls to the double bond.