Verb and Tenses

[GrammarNoob]

Hi everyone. I hope someone can help to explain the following uncertainties that I have.
Your help is much appreciated!

• 1a. I had the chance to see a famous singer perform on stage.

• 1b. I had the chance to see a famous singer performs on stage.

May I know why we should use perform and not performs in the above examples?

• 2a. I had the chance to see how a famous singer performed on stage.

• 2b. I had the chance to see how a famous singer perform on stage.

It seems to me like both of the above are correct. Am I right, and if so, is there a difference in meaning?[/b]

Thank you again!

[Alan]

1. The construction here is 'see someone DO something'. The verb takes the infinitive form.

2. (b) is ungrammatical: a finite verb form is required here.