Question: > 
> 1. Professor required his students to return their papers typed.
> 
> 
> 

vs

> 
> 2. Professor required that his students return their papers typed.
> 
> 
> 

Which of the examples is correct? Do they have the same meaning?
What is the preferred usage?

<http://oxfordlearnersdictionaries.com/us/definition/english/require> and <http://www.thefreedictionary.com/require> do not mention any usage differences

Answer: 
A. This is using the subjunctive mood and the subject form "they" of the pronoun:

*The economy requires they **return** to work.*

*That economy requires they **should return** to work.* [this is more frequent in BrE]

E.g.

> 
> Miss Winthorpe's Elopement - Page 82 Christine Merrill - 2010 -
> ‎Preview - ‎More editions
> 
> 
> You may go back, if you wish, and explain to them that economy
> **requires they return** to work
> 
> 
> \_
> 
> 
> 

B. This is using the infinitive and the object form "them" of the pronoun, as per:

> 
> re·quire
> 
> 
> transitive verb
> 
> 
> 6 : to feel or be under the necessity of (doing or being something
> specified) — used **with a following infinitive**
> 
> 
> *one does not require to be a specialist — Elizabeth Bowen*
> 
> 
> *a candidate requires to hold a … certificate — Achievement in the Gold
> Coast*
> 
> 
> Merriam Webster Unabridged Dictionary
> 
> 
> 

*The law required **them** **to return** to work.*

> 
> \*Daily Labor Report - Issues 191-212 - Page 44 1979 -
> 
> 
> Most of the employees met in the lunchroom to discuss whether the
> collective bargaining agreement negotiated by Lumber Production and
> Industrial Workers Local 2573 **required them to return to work**.\*
> 
> 
>
Both of these sentences are attempting to get at the same semantic meaning, and in my opinion, both are grammatically incorrect. Both are good examples of English speakers' generally woeful failure to understand the subjunctive and infinitive moods.

The first sentence should be thus:

> 
> Professor required his students return their papers typed.
> 
> 
> 

The "to" is totally superfluous. In this sentence, "return" is in the infinitive mood. Verbs are in the infinitive mood if they are being used as part of a noun phrase following the main verb of the sentence, which in this case, is the past-tense "required".

The second sentence should be thus:

> 
> Professor required that his students return their papers typed.
> 
> 
> 

OK, you got that right here - the verb "return" is in the subjunctive mood, indicating a hypothetical or possible scenario, but not one that is necessarily true, or happening right now. However, your question title provides an example of where this is missed, where you say:

> 
> to require that someone does something
> 
> 
> 

This is grammatically incorrect. You require that someone *do* something, not *does*. *Does* is present tense, intended to indicate that something is a fact. As you are requiring that something be done, it is not (necessarily) yet a fact, and so the subjunctive mood *do* is appropriate:

> 
> to require that someone do something
> 
> 
> 

Note that in English, the subjunctive form is *always* identical to the infinitive form of a verb. For that reason, I sometimes call it the "subfinitive" form.