Sentence Adverbs: אולי, בטח, כנראה, למרבה המזל

A manner adverb tells you how the verb happened. A sentence adverb does something else entirely: it stands outside the sentence and tells you what the speaker thinks of it — how sure they are, how they feel about it, whether it is really what it looks like. Hebrew grammar calls this element a הֶסְגֵּר hesgér, a parenthetical, and the term is worth knowing because it predicts the one thing on this page that is genuinely rule-governed: whether the word can take a ש after it.

The certainty ladder

Three more belong to the class without sitting on the ladder at all. לכאורה likh'orá (formal) says the appearance may be deceptive — ostensibly, on the face of it; אמנם omnám concedes a point you are about to argue against; and בעצם be'étsem (informal) revises what you have just said — actually, come to think of it. What בעצם does in conversation, beside באמת, is on באמת and בעצם.

בטח deserves its own line. Milog's first sense for it is glossed כמובן, ללא ספק, ודאי — "of course, without a doubt, certainly" — so the everyday "sure, obviously" is a dictionary sense rather than slang drift. It is (informal), and what it does in conversation, including the doubled reply, is on בטח, ברור, בטוח.

Placement, and the comma question

The default position is first, before the subject. Hebrew also allows the parenthetical to sit after the subject (הוא בוודאי כבר יודע) or at the end (לא קראתי את זה, למען האמת), and none of the three is marked.

The comma is worth getting right, because the advice English speakers are usually given — Hebrew doesn't fence these off the way English does — is the rule backwards. Israeli school grammar punctuates the הסגר almost exactly as English punctuates its sentence adverbs: המילים הצדדיות מופרדות בפסיקים משאר חלקי המשפט — "the side words are set off from the rest of the sentence by commas" — one after the הסגר at the head of a sentence, one on each side in the middle, one before it at the end. The carve-out is a הסגר written as an acronym (ז״ל, בע״ה), which takes none (תחביר summary, Israeli bagrut syllabus; the ויקיספר לשון textbook gives the same list of הסגר words and adds that a long one goes between dashes).

Running Hebrew is looser than its own rule, and that is the useful part: a short sentence-initial אולי, כנראה or בטח is constantly written with nothing after it, and this page prints both — לצערי לא אוכל להגיע bare, למען האמת, לא קראתי את כל המסמך with the comma. The comma is correct and, in practice, optional; the error to avoid is not putting one in, but believing the rule runs the other way.

Which ones take ש

Some members introduce a full clause with ש, and some cannot. The test is what part of speech the word is underneath.

The left column are predicates — ייתכן is a verb, ברור an adjective, מזל and חבל nouns — and a predicate needs a clause to be predicated of, which is what ש delivers. The right column are הֶסְגֵּר parentheticals: they comment on a sentence that is already complete, so there is nothing for ש to attach to.

כנראה ש and כמובן ש sit exactly on that line, and they are the reason the class matters. The Academy of the Hebrew Language holds that both are not recommended, and its reason is this one exactly: תפקידן של המילים ׳כנראה׳ ו׳כמובן׳ במשפט הוא הסגר – חלק תחבירי שמוסיף את יחסו של הכותב לנאמר במשפט, ולכן אין מקום להוסיף להן את מילת השעבוד ׳ש׳ — "the role of the words כנראה and כמובן in the sentence is הסגר, a syntactic part that adds the writer's attitude to what the sentence says, and so there is no room to add the subordinator ש to them." The structures it recommends instead are כנראה with no ש or נראה ש, and כמובן or מובן ש. (Quoted from the Academy's official posts of 27 July 2022 and 28 April 2024, and reported in the same wording in the press the next day, 28 July 2022; the Academy's own site blocks direct retrieval, so there is no ruling page to link.)

Whether writers obey it is worth checking rather than assuming, and largely they do. Counting Hebrew Wikipedia with insource:/…/ regex searches on 15 August 2026: the proscribed כנראה שה־ returns 322 articles, while נראה שה־ not preceded by a כ returns roughly 3,600 — a count that size is a floor rather than a figure, so take the ratio, about eleven to one for the recommended form. The other pair is closer and points the same way: כמובן שה־ returns 104 against 185 for מובן שה־ without the כ. Write כנראה or נראה ש and you are both correct and in the majority — but read כנראה ש without blinking, because there are still 322 articles of it.

Several of them are not words at all

Here is the observation that removes a real comprehension drag at B2. A good part of this class is made of frozen prepositional phrases — they have internal grammar, and you should ignore all of it.

Common Mistakes

1. Dropping the ש after ייתכן. The words around it on the ladder take none, so it falls off by analogy.

2. Dropping the ש after מזל and חבל. English lucky you came and what a shame you're not coming have no that in them at all.

3. Using לכאורה for "apparently". Both English words start the same way, and the Hebrew pair does not overlap at all.

4. Inflecting a frozen phrase. English says luckily for me, so the Hebrew phrase gets a possessor bolted onto it.

Key Takeaways

• A sentence adverb is a הֶסְגֵּר: it comments on the whole proposition from outside it, and it never modifies the verb.
• The ladder runs from בוודאי, בהחלט, כמובן, אכן and בטח at the certain end, through כנראה in the middle, down to אולי and ייתכן ש at the bottom. לכאורה, אמנם and בעצם belong to the class but sit off the scale.
• Default position is first, and after the subject or at the end are both unmarked. The comma is normatively correct and optional in practice — Israeli school grammar sets a הסגר off with commas on both sides, and drops them only when it is an acronym (ז״ל). The common advice that Hebrew never uses them is the rule backwards.
• Predicates take ש (ייתכן ש, ברור ש, מזל ש, חבל ש, מובן ש); parentheticals do not (אולי, כנראה, לכאורה, אמנם, בהחלט).
• The Academy holds כנראה ש and כמובן ש to be not recommended, on exactly that reasoning — and edited writing has largely followed it. On Hebrew Wikipedia the recommended נראה ש outnumbers כנראה ש by roughly 11 : 1, and מובן ש beats כמובן ש 185 : 104.
• בטח meaning "of course" is a dictionary sense, not slang drift — Milog's first gloss for it is כמובן, ללא ספק, ודאי. It is informal.
• למרבה המזל, לצערי, למען האמת, בסופו של דבר are frozen phrases. Learn them whole; parsing them word by word is what makes them hard to hear.