require typographical (curly) apostrophe (’)

If you wrote "Im not sure," fix it to "I'm not sure." The problem is a missing apostrophe - or the wrong apostrophe style - not the meaning. Spotting and correcting that small mark improves clarity and polish.

Quick answer

Write "I'm not sure" (or "I am not sure" for emphasis). "Im not sure" is usually a typo.

Missing or wrong apostrophes are common when typing fast or on devices without smart quotes.
Check the whole sentence - context often shows whether you meant the contraction or the full form.
In formal writing prefer the correct punctuation and, where typography matters, typographical (curly) apostrophes.

What went wrong?

"Im not sure" drops the apostrophe that marks the omitted letter: I'm = I + am. Readers see the gap as a typo or careless copyediting.

Sometimes the error is a punctuation character: a straight apostrophe ' (typewriter style) appears instead of a typographical (curly) apostrophe '. Both mark the contraction, but the curly form looks cleaner in published text.

Straight apostrophe vs typographical apostrophe

Two common glyphs do the same job but look different:

Straight apostrophe: I'm (uses ')
Typographical (curly) apostrophe: I'm (uses ')

Typographical apostrophes are standard in printed and polished digital text. Most editors and word processors will convert straight quotes to "smart quotes" automatically; if they don't, replace them manually.

Contraction choices and spacing

Decide between the contraction "I'm" and the full form "I am" based on tone. Use "I'm" for conversational or concise sentences, and "I am" when you want emphasis or formality.

Correct contraction: I'm not sure. (closed form, single word with apostrophe)
Full form: I am not sure. (two words, no apostrophe)

Hyphenation doesn't apply here, but spacing does: don't insert spaces around apostrophes (not I ' m, not I 'm).

Why writers make this mistake

Common causes:

Typing quickly and skipping the apostrophe.
Relying on speech memory - contractions sound right but get written incorrectly.
Devices or editors that don't auto-convert straight quotes to curly ones.
Copy-pasting from sources that strip punctuation.

How it looks in normal writing

Seeing correct and incorrect forms in context helps you spot the error in your own drafts. Below are practical examples across work, school, and casual settings.

Wrong vs right examples you can copy

Wrong:
Work: The migration looks Im not sure by Friday.
Right:
Work: The migration looks I'm not sure by Friday.
Wrong:
School: The final draft seems Im not sure with one more revision.
Right:
School: The final draft seems I'm not sure with one more revision.
Wrong:
Casual: Dinner at six is Im not sure for me.
Right:
Casual: Dinner at six is I'm not sure for me.
Wrong: Don't vs Dont: Dont forget to bring your umbrella.
Right:
Correct: Don't forget to bring your umbrella.
Wrong: Possessive: The dogs collar was dirty.
Right: Possessive: The dog's collar was dirty.
Wrong: Curly vs straight: He said 'I'm ready'.
Right: Typographical: He said 'I'm ready'. (or He said "I'm ready.")

Try your own sentence

Paste the whole sentence into an editor or the widget below. The surrounding words usually make the intended form obvious.

How to fix your own sentence

Fixing is usually quick but check tone and flow afterward.

Step 1: Identify whether you mean the contraction (I'm) or the full form (I am).
Step 2: Insert the apostrophe and choose straight or typographical style as appropriate.
Step 3: Reread the sentence to ensure the replacement sounds natural.

Rewrite:
Original: This plan is Im not sure if everyone stays late.
Rewrite: This plan is fine if everyone stays late. (or) This plan is I'm not sure about if everyone stays late.
Rewrite:
Original: The assignment feels Im not sure now.
Rewrite: The assignment feels uncertain now. (or) I'm not sure about the assignment now.
Rewrite:
Original: Is that Im not sure this afternoon?
Rewrite: I'm not sure about that this afternoon. (or) Is that happening this afternoon? I'm not sure.

A simple memory trick

Visualize the contraction as the two words joined by a missing letter: I'm = I + (a)m. That mental image makes the apostrophe easier to remember than a fragmented, spaced version.

Train your eye by scanning drafts for common missing-apostrophe patterns.
Search for " Im " (space-I-m-space) or "Im " at line starts to catch duplicates quickly.
Fix in bulk when you find repeated mistakes.

Similar mistakes to watch for

Once you miss one punctuation mark, nearby errors often follow. Check for these patterns:

Other split or fused words (e.g., "alot" vs "a lot").
Missing apostrophes in possessives (students' vs student's).
Straight quotes where typographical quotes are expected.
Wrong verb forms that hide behind punctuation errors.

FAQ

Is "Im not sure" ever correct?

Not in standard written English. It appears in very informal chat, but the correct contraction in writing is "I'm not sure."

Should I use a straight apostrophe or a curly one?

Both indicate the contraction, but curly (typographical) apostrophes (') look better in published or formal text. Many editors convert them automatically.

When should I write "I am" instead of "I'm"?

Use "I am" for emphasis or a formal tone. Use "I'm" for flow and brevity in casual or conversational prose.

How can I find these mistakes in long documents?

Search for common patterns like " Im " or missing apostrophes after single-letter words (I, a). A quick scan for words like Dont, Im, Hes, Shes will catch many errors.

Can a spellchecker catch this?

Spellcheck catches some cases but not all. Sentence-level review reveals whether a contraction fits the context and whether punctuation style needs adjusting.

Check the whole sentence before you send it

Small punctuation errors stand out once you read the complete sentence. Pause to scan sentences for missing apostrophes and inconsistent quote styles before sharing or publishing.