Adding emphasis

What I did was send her a bunch of flowers

It is sending her flowers what I do

What he should do is avoid antagonizing her.

It's him that should avoid antagonizing her.

What surprised me was his uncompromising attitude.

Why surprised me was his uncompromising attitude.

reckless driving is something what worries me.

It is his reckless driving that worries me.

When she quit her job she felt terrible.

It was quitting her job that she felt terrible about.

What she did was fire him.

Fired him is what she did.

What really annoys me is his bad manners.

His bad manners are really annoying.

It was last week that he proposed to her.

Last week was the proposal.

It was Sam and Jo that went to Brazil on their honeymoon.

Brazil was Sam and Jo honeymoon destination.