Difference between "I love you" and "I do love you"

I’m really confused, always find the sentences that constitute the word of “do” before the verb. What is the difference between the meaning of sentence with “do” and without “do”? I give the example below.

  1. I love you.
  2. I do love you.

Hi Salmonella,

The use of ‘do’ in an affirmative sentence is emphatic. You should not use it regularly. Save it for situations in which there is a need for special extra emphasis in your statement.

[size=75]“In nature, the emphasis is in what is rather than what ought to be.” ~ Huston Smith[/size]

I 've ever asked to my English teacher at my English course forum, what’s the difference between, I Love you and I do love you? He replied, I do love you, it’s used for giving more stressing to how deep our love to another one. I love you, shows that the statement is likely flat. I do love you, shows that our feeling is deeper and we have more meaningful intention by expressing it. Maybe from this forum, there’re another ones who can explain it more clear with appropriate definition.

I do love you ( I strongly emphasize my LOVE because you are not sure of my feeling)

I do hate telling lie. I do my best to help.

‘I do my best to help.’ has a different ‘do’, Jimic.

Do does not necessarily signify the emphatic mood in English. There are different ways of expressing the emphatic including use of adverbs like ‘really’ but more than anything English expresses the emphatic mood via tone and stress (using your voice to add emphasis). You can emphasis any component of a sentence this way. For instance, ‘I’ love you! (emphasis on I versus someone else loving) I love YOU! (emphasis on who the person loves) I LOVE you! (emphasis on love versus say like).

There is technically no difference between ‘I love you’ and ‘I do love you’.

Every sentence in English has at least two verbs. The first one (or if you look at a sentence the left-most verb) expresses agreement with the subject for person and number and in most often also tense; this verb is called an auxiliary. The right-most verb in a series is used to convey the idea of the of the sentence and is called the vector. Some sentences have more than two verbs together. In this case you’ll have multiple auxiliaries with a single vector (such as I should have been working – with should, have, and been being auxiliaries and working being the vector). There are more possibilities for more complex sentences such as two different sets of auxiliaries and vectors or one set of auxiliaries having two vectors and so on. But, in the simplest forms, a sentence has an auxiliary and a vector.

There are different types of auxiliaries:

Aspectual Auxiliaries: used to express aspect (‘do’ for non-durational aspects and ‘be’ for durational aspects). The verb that follows an auxiliary (immediately to its right in the sentence) is called its subordinate. Different auxiliaries require their subordinates to take on certain forms. ‘Do’ takes the finite verb as its subordinate (this is the form just like in the dictionary). ‘Be’ requires its subordinate to be a present participle (the -ing form).* Aspectual auxiliaries take the position to the immediate left of the vector.

  • when ‘be’ is used as an aspectual auxiliary but when used to mark the passive voice, it requires its subordinate to be the past participle (third form of the verb: eaten, risen, shone, etc).

Perfecting Auxiliaries: In English there is only one and that is ‘have’ which requires its subordinate to be a past participle. When used to perfect a verb in the non-durational aspects, ‘have’ replaces ‘do’ and then subordinates the vector into past participle form. When used to perfect a verb in the durational aspects, ‘have’ subordinates ‘be’ but does not displace it, occupying the position immediately to the left of the aspectual auxiliary and subordinating it to the past perfect form ‘been’.

Modal Auxiliaries: any other auxiliary that expresses mood is called a modal auxiliary. Modal auxiliaries can be a single verb with only one form (should, can, will, shall, must), a verb phrase that can have multiple forms (have, be able, be going, dare), or even special phrases or structures that combine with the subject (let’s). There are more specific rules about modal auxiliaries, but the basics are that most modal auxiliaries can subordinate other modal auxiliaries but others cannot, but that all modal auxiliaries can subordinate perfecting and aspectual auxiliaries. Again, because ‘do’ is a “weak auxiliary”, it is always displaced by other auxiliaries including all modal auxiliaries. Thus when a modal auxiliary is used in a non-durational aspect, ‘do’ disappears and the modal auxiliary subordinates the vector directly. Some modal auxiliaries require their subordinate to be a finite verb while others require the subordinate to add ‘to’.

OK, those are auxiliaries.

Now, every sentence has at least one auxiliary and at least one vector as part of the verb (verb as in function within a sentence, not as in part of speech). In affirmative statements in the indicative mood (neutral mood) in non-durational aspects in English, the aspectual auxiliary ‘do’ may be “omitted” and its ending inflected into the vector (do + walk = walk [zero ending]; does + walk = walks [3rd person “-s” ending]; did + walk = walked [past tense -d ending]. For irregular verbs combining ‘did’ results in an even more specific form without an ending (did + eat = ate). In these sentences, it’s not that there is no ‘do’, it’s just that it’s hidden. There is no difference in meaning between the periphrastic form (meaning the version with separate parts does+eat) and the inflected form (eats). In all other types of sentence except for affirmative statements (yes answers), the inflected form is not allowed. This is why there is a ‘do’ in questions and negatives and short answers and such even when there doesn’t seem to be a ‘do’ in affirmative statements.

Back to the original question: No, there is no difference at all between “I do love you” and “I love you” because the second version is simply linguistic shorthand for the first version.

However, in the first version there are four words. Emphasis could be added to any of those words as described above. If “I do love you” is a response to “Do you love me?” then that emphasis could be placed on the ‘do’ to overemphasize that his answer is not only affirmative but that it is in response to the previous question (because it’s like restating the short form answer “I do” within the longer form “I do love you” or “I love you”). So “I DO love you!” is an emphatic sentence in which do gets the target of that emphasis but even there, it’s not ‘do’ expressing the emphatic, it’s the stress of the voice (or in this case my using all capital letters) that does.

Sorry for the really long answer, but so few people seem to understand how this all works.

@Jimic: You said…I strongly emphasize my LOVE because you are not sure of my feeling…It means: We say I DO LOVE YOU, for convincing another one, that we TRULY love him/her?

James is correct.

In “I do work hard,” ‘do’ is acting as the aspectual auxiliary and ‘work’ is the vector.

In “I do my best to help,” the aspectual auxiliary is also (do) but it’s been omitted while the ‘do’ you see in the sentence is actually the vector. You can tell this is the case because if you make this a question you’d have to say “Do I do my best…”. “To help” is a prepositional phrase telling how or why the subject does his best.