There is no clear answer to the question posed in the title. It all depends on which member of the proposal is "probably." Commas are punctuation marks with which a writer in Russian always has difficulties. And the given word can be either an introductory or just an adverb. Let's understand in more detail.
About introductory constructions and words
In speech, a person often wants to express his attitude to the spoken. This is done with the help of introductory constructions and words: according to others, no doubt, fortunately, as usual, by the way , etc. On the letter they are always highlighted with commas, and on both sides, if they occupy a place in the middle of a specific sentence. How to distinguish that a word or phrase is introductory? There are three main signs:
- The remaining members of the sentence are not associated with this word or phrase, it is impossible to ask a question from them.
- They are always easy to replace with other introductory constructions or synonyms. For example: I did not hear her, or rather, I could not even hear, because she spoke too quietly (or rather, more precisely, more correctly) .
- If the introductory construction is removed, the meaning of the sentence will still not be lost.
"Probably" is highlighted with commas if it has the above characteristics and is an introductory word:
- I’m probably going to the village tomorrow.
Introductory words: meanings
There is another clue that we have before us an introductory construct or word - the meaning that they play. The main ones are listed in the picture a little higher, and examples are given in the following table.
| Value | Introductory words | Examples |
| 1. Assessment of confidence or uncertainty, expression of the degree of reliability of facts | Of course, it is indisputable, true, authentic, no doubt (certainty); probably, perhaps, perhaps, I suppose, in some way, it should be, apparently (uncertainty) | He, of course, understood that this activity was not legal. Perhaps she should not have come. |
| 2. Expression of feelings | Fortunately, to joy, to her pleasure (approval); to trouble, a sinful deed, to regret (regret); amazing business, strange, incomprehensible business (surprise); what good, the hour is uneven (fear); in fact, except for jokes (expressive) | How deliberately, she did not bring her passport with her. Petrov, to the surprise of his colleagues, did not congratulate the leader on his birthday. |
| 3. Source of information | In my opinion, they say, as it turned out, from the point of view of science | According to friends, she did not wait for him. |
| 4. Call for attention | Remember, let me listen, agree | You can go alone if you want. |
| 5. Characterization of the way thoughts | In a word, it’s easier to say, firstly, by the way, to say, as usual | So, I first decided to graduate. |
A comma is needed next to "probably" if this word is used in one of the listed meanings. And in which one, we will learn further.
"Probably" as an expression of uncertainty
Speaking about introductory constructions, one should know that there are words that are used only as introductory ones: apparently, therefore, therefore, by the way , etc. But most of them can be used not only in these constructions or independently, but also be part of speech, such as a parsed word.
“Probably” is highlighted with commas if it is an introductory one. In this case, it characterizes the speaker’s uncertainty or some uncertainty. In this case, the words-synonyms can be the words: “ probably”, “apparently”, “perhaps ”. Here is an example where “probably” is an introductory word. A comma is placed both at the beginning and after it:
- She probably still cannot forget her feelings for him.
What parts of speech do introductory words express?
Absolutely different, including complex grammatical forms:
- Nouns. Fortunately, she did not have time to go far .
- Brief adjectives. Really, I didn’t think about the consequences .
- The same part of speech is superlative. Most importantly, it is necessary to find a way out of this situation.
- Pronouns. She, meanwhile, managed to read the text of the letter.
- Verbs. They say mushrooms will go soon.
- Combinations of verbs with adverbial participles. In short, he tricked you.
- Impersonal sentences . It seemed to her that she was not alone in the room.
- Two-part sentences. As far as I can remember, my aunt always wore hats.
- Uncertain personal offers. As they talked about her, she was an honest and kind girl.
And what part of the speech is the introductory word "probably" (commas in this case are required)? This is an adverb, which, incidentally, is often used in water structures (no doubt, of course, rather ), but can also act as a member of the proposal.
Commas: "probably" is a member of a sentence
If "probably" acts as an adverb, then there is no need to highlight it with commas. By the way, you should know that this is a rather outdated form and is often used without the letter "e" at the end:
- I probably know about it now.
- Now I can probably judge him.
The word was actively used in the XIX century, therefore it is found in literary works of classics. Currently, speech is used extremely rarely. If "probably" is a member of the proposal, then it is easy to replace it with synonyms. In the context, these can be adverbs: “for sure”, “necessarily”, “undoubtedly”, “true”. The antonyms in this case are the words: "impossible", "incredible."
In the above cases, a comma after "probably" is not required, as well as before the word.
Main conclusions
The word under study can act as both an introductory and a full member of the sentence. In the latter case, it answers the question: “how?” and most often refers to a verb, indicating a sign of action:
- Does he know how? - He probably knows .
In this embodiment , punctuation is not required. To be sure, you can always pick up adverbs-synonyms.
When the word "probably" acts as an introduction, the commas are placed, highlighting it on both sides. At the beginning or at the end of a sentence, one punctuation mark is required.