considered her to be, as, was

[Passionwagon]

"She considered him to be the problem."
"She considered him as the problem."
"She considered he was the problem."

The first two sound fine to me, the first sounds the most conventional and familiar to the ear, though I'm quite sure the second is also fine.

The third sounds ambiguous to me, as "considered" could mean either "thought about the idea that..." or "viewed that..."

However, what about these sentences:

"She considered the main problem to be her boss." (this one is fine)

"She considered the main problem was her boss." (does this make sense?)

[Tdol]

The third option sounds OK to me (BrE speaker).

[Philly]

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I also feel uncomfortable with the third one (AmE), though I wouldn't say it's wrong.

And I've heard people say "considered as" often enough, but I think you can just omit the word as: "She considered him the problem."
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