Subject + be used to + verb

No.

It should be "used to categorize". "Ergative" should also be in quotes or italics,* since it is a mention of the word.

* I mean, so as to contrast with the rest of the sentence. Obviously as you have written it, it is in italics, but only because the whole sentence is in italics.

Isn't "to" there a preposition?
Yes you are right about the fonts. But I'm not able to edit it now!

KhoshtipManIsn't "to" there a preposition?

No. It's the infinitive marker to, not the preposition to.
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CJ

KhoshtipManIsn't "to" there a preposition?

Not when "used to" means "used in order to", no. This "to" introduces a verb infinitive.

When "used to" means "accustomed to", "to" is a preposition. For example, you can say "used to categorising" if you mean "accustomed to categorising". In speech this "used to" has soft "s", as opposed to the hard "s" of t

GPYNot when "used to" means "used in order to", no. This "to" introduces a verb infinitive.When "used to" means "accustomed to", "to" is a preposition. For example, you can say "used to categorising" if you mean "accustomed to categorising".

Good explanation, thanks.

First: I have heard that in forms like "Subject + be/get used to + verb", to i

KhoshtipManSecond question: How do you generally recognize which to is or is not a preposition in sentences? Is there any tool to?

See and follow the links. It may help.
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CJ

KhoshtipManFirst: I have heard that in forms like "Subject + be/get used to + verb", to is a preposition

As before, it depends on which "used to" is meant (and on what you are allowing as a "verb").

If "used to" means "used in order to", e.g. "Explosives were used to blow open the safe", then "to" is an infinitive marker.

If "used to" means "

Good explanation GPY, as usual. Thanks.
To summary:
I can use the factor "in order to" for the forms "Subject +be/get used to + verb" and if that factor is meaningful there, so to is a pert/marker of infinitive and f not, so the to is a preposition. Agree?

CalifJimSee 'To' + 'ing' and follow the links. It may help.

Thanks. It helped. But I'd like to find a means by which I determine the preposition to in sentences. It's rather easier to memorize than those many instances. Not?

I can recall months ago I asked this question and like now was looking for a so-called means. At the time, CB gave a fine

KhoshtipManI can use the factor "in order to" for the forms "Subject +be/get used to + verb" and if that factor is meaningful there, so to is a pert/marker of infinitive and f not, so the to is a preposition. Agree?

Yes, I think that's correct.

I'm not sure what "pert" is supposed to mean though. A strange typo for "particle" is all I can think ...