"to be"

[guest]

I've notice a lot of GMAT idioms where "to be" is incorrect
eg.
"consider to be" should be consider xy
"regarded to be" should be regard as

Is there a general rule when using the phrase "to be" is correct?

Many thanks

[esledge]

Unfortunately, no. The lack of a general rule is what makes idioms idioms.

Here are some that require (or at least accept) the "to be":
Our cat Gunther was estimated to be 16 years old.
Phillip claims to be heir to the throne.
Though almost finished with law school, she is disinclined to be/become an actual lawyer.