Your friend is correct. "I need compute ..." is ungrammatical, but "I need only compute ..." is fine, if a little bit old-fashioned and formal.
Modal verbs do not use a "to". That is, you say
I can do this.
The verb "need" is a funny case; it is only modal in the negative. In the positive, we already have an equivalent modal verb; namely, "I must". ...
The reality of the language is such that both forms are used, on both sides of the Atlantic, but the bare-infinitive form is clearly preferred, as the stats from the Corpus of Contemporary American English (COCA) and the British National Corpus (BNC) illustrate:
all you have to do is [inf] 842 72
Quirk et al is a good grammar but weak, I think, on complex sentences.
What we're looking at in all of these examples is the remains of deceased clauses.
Of the four sentences, two:
I saw her leave the room
I heard someone shouting
are examples of special constructions that are limited to sense verbs, one with an infinitive and the other with a gerund. ...
EDIT: Added modals including quasi-modals; added examples and exceptions; note that these lists are only “complete” for the modals and quasi-modals.
That’s because make does not take a to-infinitive. It takes a bare infinitive, without the to particle. Not all infinitives have a to attached to them. You really have to learn the sort of complement each ...
The verb go can take a bare infinitive following. So can come. (Edit: And sometimes, so can run.)
Examples: You can go get your hair cut or come get your supper, you can go see a movie or come see what I’ve got, you can go wash you car or come wash your hands, and you can go plow the field or come milk the cows with me. Or you can just plain go hang.
There's something missing from the description of the problem, which is the omission of the word only. I grant that it is an archaic construction, but I do not concede it is incorrect.
1. In this setting, we need only consider X.
We could equivalently say
2. In this setting, we only need to consider X.
I agree that the ...
Try replacing have to with must...
2: What you must do is read a lot.
Not only does the first to disappear; the possibility of including a second one vanishes too.
I think it's easier if we assume these sentences are "cut down" versions of the [hypothetical]...
1a: All you have to do is you have to read a lot.
2a: What you must do is you must read ...
EDIT FOLLOWING A MORE ATTENTIVE READING OF THE QUESTION
The short answer is ‘No’ A marked infinitive is obligatory, as may be seen from counter-examples:
✲What we plan is take the train to New York.
✲Caesar’s objective was break the power of the Druids.
The question then becomes, Why is the bare infinitive acceptable in your two examples?
I note ...
SUMMARY: While Americans don’t always have to use the to after ought in negative contexts, the English apparently must do so everywhere, even negatively.
The word ought can today act as a true modal auxiliary only in negative contexts, which includes interrogative ones albeit in a super-formal register.
By true modal, I mean it acts exactly like must does ...
No, not in the same way, but then need and dare are both a little different, anyway.
Need and dare have several peculiarities:
They take infinitive complements, like many other verbs, in the affirmative and negative
He wanted to read it. He didn't want to read it.
She needs to see them. She doesn't need to see them.
He dared to contradict them. He didn't ...
The OED provides for no such usage. Adapting the examples:
1) Tend can be used with to/towards.
Walter tended to run.
Walter tended towards corpulence.
... tends towards infinity.
2) Tend can be used with an adverbial:
fire is hot and tends upwards
No dictionary seems to provide for a usage like:
... tend be ...
Verdict: typo or ...
In this case make is not the causative, which as you say takes an infinitive marked with to. We are not causing 'it' to work.
Instead, make is employed in the idiom make it to [a place]:
Make it means, approximately, succeed at or achieve success.
To is the ordinary preposition.
Work is not a verb but a noun, the object of the preposition: our job, the ...
Both are grammatically correct. The first is the one I'd use and is the idiomatic one. The second sounds fine and there's nothing wrong with it, but only less idiomatic and that's why you don't see it in your written materials. In addition to that, the to in there is unnecessary and doesn't really add anything to the overall meaning of the sentence. Most ...
You are confusing two very different English idioms using HAVE† + VERBinfinitive
In the construction with the marked infinitive (to VERB), HAVE has a modal sense, approximately equivalent to must.
My car has to be fixed. = My car must be fixed.
Don has to fix my car. = Don must fix my car.
My car has to be fixed. = My car must be fixed.
In addition to badroit's excellent answer:
Tend be is unplottable on an NGRAM.
If you are unfamiliar with its use, an NGRAM is a search for a word form or string within an entire corpus of literature which can compare its relative prevalence (statistical probability of occurrence). When asking a question of this type, plotting an NGRAM can often help ...
Seem here is the infinitive. It, anyway, is an object, not a subject (consider: her hat makes her seem aloof, not makes she seem aloof).
The infinitive, appearing without the preposition to, is called the bare infinitive. A discussion can be found here: http://www.grammaring.com/make-object-bare-infinitive
What is special about the modal auxiliary 'ought' is that it takes the 'to infinitive' after it.
from English Grammar Today (http://dictionary.cambridge.org/grammar/british-grammar/modals-and-modality/ought-to)
Ought to is a semi-modal verb because it is in some ways like a modal verb and in some ways like a main verb. For example, unlike modal ...
The passive forms, though queried by Quirk, are used.
"I was helped clean" shows 3 Google hits.
"I was helped to clean" shows 2950 Google hits. (at my space-time coordinates)
This is how I felt the breakdown would be.
While I have no problem in accepting both "I helped clean" and "I helped to clean" as equally grammatical, I feel the bias in favour (...
English definitely requires an "and" between imperatives, except in certain cases. The phrase "Go [imperative]" is somewhat idiomatic, which is why "Go fuck yourself" or "Go have fun" are perfectly grammatical. However, no other verbs that behave this way are coming to mind. In most other situations, the 'and' is obligatory.
For example, "Sit and eat your ...
The infinitive read
-- or to read if the complementizer to is retained (it's optional) --
is correct, and the gerund reading is not correct.
This is what's called a Wh-Cleft sentence (also "Pseudo-Cleft"); it's a variety of Clefting, which is a syntactic device to emphasize certain parts of sentences. Clefts come from simple sentences like
I want to read ...
This is more a matter of style than grammaticality, but the whole point of the bulleted list is to explicitly make use of a parallel structure to eliminate repetition, so it seems rather silly to include a repetitive element that you could have pulled out.
The bare infinitive is used because the construction used is: have [someone] do [something]. This is a special use of the verb have, which means something like "order or cause someone to do something".
She had me copy the documents.
They had her remove the lens cap.
The verb recommend can be constructed with a noun as an object:
I recommend ...
Collins Cobuild English Usage (p567) states:
You can use would rather followed by a clause to say that you
would prefer something to happen or to be done. In the clause you use
the past simple tense.
Would you rather she came to see me?
May I go? - I 'd rather you didn't.
Practical English Usage (p492) has a rather more nuanced entry:
We can use would ...
Just because one verb can follow another in the bare infinitive form does not automatically make the former verb a modal, nor does the lack to the to particle somehow make the latter verb a finite verb.
Help is not a modal verb because modal verbs are not subject to changes of inflectional morphology due to person or number (or arguably by tense). Since ...
The short answers:
Q1 — "watched her dance" and "watched her dancing" are both acceptable. There are slightly different connotations but the meaning is clear. Pragmatically, they mean the same thing.
Q2 — "strike the pole" and "striking the pole" are both acceptable. There are slightly different connotations but the ...
'Make it to' is a phrasal verb here, it's used to express the idea of arriving somewhere, which may have been difficult.
I need to make it to the bus stop on time, or I'll lose my job!
She made it to her friend's house with no problems, the traffic was very calm that day.
I made it to the finish line in 1st place! It was my 10th marathon.