[Grammar] Usage of "to be"

[tangomania]

What is the name of grammar structure of "to be" in this sentence?

Can somebody explain the usage of "to be" in this sentence?

Example: He is known to be a madtv funnyman.

Actually, I know what this sentence means, but I can not understand the usage of "to be" in the sentence.

 

[billmcd]

"to be" = to exist as/to have the characteristics of (a mad tv funnyman)

 

[Raymott]

What is the name of grammar structure of "to be" in this sentence?

Can somebody explain the usage of "to be" in this sentence?

Example: He is known to be a madtv funnyman.

Actually, I know what this sentence means, but I can not understand the usage of "to be" in the sentence.

It's the infinitive. It works for all verbs. The main verb is "known" here. Look at these:

He's known to walk like a duck.
He's said to understand the meaning of life.
He's thought to be a wizard.
I promise to be there at 8pm.
I promise to take you to the movies.

 

[tangomania]

thanks. I got it.