Conditional Simple / Perfect Conditional

Conditional Simple

 1. Use 

We use it for something that might happen.

We use it in the main clause in type II of the Conditional sentences.

2. Form

would + infinitive

3. Examples

I would travel by plane
He would not go there. He woudn't go there
She'd work harder
Would you come with me?

Conditional Perfect

1. Use

We use it for something that might have happened in the past.
We use it in the main clause in type III of the if clauses.

2. Form 

would + have + past participle

past participle → (infinitive + -ed) or (3rd column of the table of the irregular verbs)

3. Examples

I would have gone to the party if you had invited me.
She would not have done it. She wouldn't have done it.
Would they have taken part in the competition?