"of" and "that" with "when", "why", "where"?

[dihen]

Are these all incorrect?

"I have no idea of what he was talking about."
"I have no idea about of what he was talking."

"the suggestion of that we leave early"

"the place of where they used to live"

"the time of when he goes to work"

"the reason of why he didn't come"

"I know that why he did this."
"I know that what I should do."
"I know that how I can help them."
"I know that what you want."
"I know that who did this."
"I know that who(m) I saw."
"I know that whose book it is."

[Tdol]

Yes

[dihen]

Would native speakers ever use any of those?

[dihen]

Originally Posted by tdol

Yes

Even this one?
`
I have no idea of what he was talking about.
`
Then why is this correct?
`
have an idea of what is right and what is wrong

[dihen]

Please answer me.

[lapiz]

I think that in the sentence
I have no idea about of what... you are putting together 2 prepositions, apart from that the pattern is (about sth) not about of....

[Coffa]

Originally Posted by dihen

Please answer me.

Yes. "I have no idea of what he is talking about" is grammatically correct, though native speakers would usually omit 'of'.