Ordinal Numbers worksheet with sentences to complete using correct ordinal numbers, ideal for educational practice.

Here’s the completed worksheet with correct ordinal numbers filled in, along with explanations for each answer:

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Ordinal Numbers

Complete each sentence with the correct ordinal number.

1. My sister is one year old today. It is her _first_ birthday.
→ *Explanation:* When someone turns 1 year old, it’s their first birthday — the very first time they’re celebrating a birthday.

2. I am the youngest of three kids. I am the _third_ child.
→ *Explanation:* If there are three children and you’re the youngest, you’re the last one born — so you’re the third child (oldest = 1st, middle = 2nd, youngest = 3rd).

3. I am number five in line. I am _fifth_ in line.
→ *Explanation:* “Number five” means your position is 5th → ordinal form is fifth.

4. I am rethinking it. I am having _second_ thoughts.
→ *Explanation:* This is a common idiom: “having second thoughts” means you’re reconsidering or doubting a decision. The phrase always uses second, not “first” or “third”.

5. We are house number four. We are the _fourth_ house.
→ *Explanation:* If your house is numbered 4 on a street, you are the fourth house in sequence.

6. Step seven is the hardest. The _seventh_ step is hardest.
→ *Explanation:* “Step seven” → ordinal form is seventh.

7. They’ve been married eight years. It’s their _eighth_ anniversary.
→ *Explanation:* After 8 years of marriage, it’s the eighth anniversary — counting from the first year as “first anniversary”.

8. Step six confuses me. I get confused by the _sixth_ step.
→ *Explanation:* “Step six” → ordinal form is sixth.

9. I finished as number ten. I was _tenth_ across the finish line.
→ *Explanation:* If you were number 10 to finish, you came in tenth place.

10. This is cookie number nine. It’s the _ninth_ cookie.
→ *Explanation:* “Cookie number nine” → ordinal form is ninth.

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✔ Final Answer Key:

1. first
2. third
3. fifth
4. second
5. fourth
6. seventh
7. eighth
8. sixth
9. tenth
10. ninth

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📌 Tip for Students:
Ordinal numbers tell position or order (like 1st, 2nd, 3rd). To make them, usually add “-th” to the number, but watch out for exceptions:
- 1 → first
- 2 → second
- 3 → third
- 5 → fifth (drop the ‘e’)
- 8 → eighth (add ‘h’)
- 9 → ninth (drop the ‘e’)
- 12 → twelfth, etc.

Hope this helps! 😊