Out of the following ten sentences, 5 of them are correct in their use of apostrophes. Simply write the numbers of the five sentences that are correct. .

The five sentences that I choose were correct were 3,4,6,7, and 8

Is this correct?

Canada’s mens’ hockey team wins gold medals almost every year.
Lets forget that we tried to build a racing car because it’s been an awful experience for us and our friends.
The woman’s skin was raw where her boots had rubbed against her heels.
The country’s top leader attended the international conference last year.
It’s time to buy new books for our classes next semester.
Since the schools’ homework club began, my grades have improved.
The boy's father said the baseball was his son’s but we knew it was ours.
After three days’ worth of work, they completed the project.
There are three pieces’ of pie left,
We always have a big birthday party on my mothers birthday.

I changed my answers the correct ones are 3,4,5 7 and 9

It would have helped if you had numbered the sentences.

1.Canada’s mens’ hockey team wins gold medals almost every year.
2. Lets forget that we tried to build a racing car because it’s been an awful experience for us and our friends.
3. The woman’s skin was raw where her boots had rubbed against her heels.
4. The country’s top leader attended the international conference last year.
5. It’s time to buy new books for our classes next semester.
6. Since the schools’ homework club began, my grades have improved.
7. The boy's father said the baseball was his son’s but we knew it was ours.
8. After three days’ worth of work, they completed the project.
9. There are three pieces’ of pie left,
10. We always have a big birthday party on my mothers birthday.

the correct ones are
3, yes
4, yes
5, yes
7, yes
9, no

Then my other answer would be 8 is correct

Yes, 8 is correct.

Out of the ten sentences provided, the five sentences that correctly use apostrophes are:

3. The woman’s skin was raw where her boots had rubbed against her heels.
4. The country’s top leader attended the international conference last year.
6. Since the schools’ homework club began, my grades have improved.
7. The boy's father said the baseball was his son’s but we knew it was ours.
8. After three days’ worth of work, they completed the project.

To determine if a sentence correctly uses apostrophes, you need to look for possessive nouns or contractions. Possessive nouns indicate ownership or possession, and they are formed by adding an apostrophe and an "s" ('s) to singular nouns or just an apostrophe (') to plural nouns that already end in "s."

In sentence 3, the correct use of an apostrophe is demonstrated by "woman's" to show that her skin belongs to her.

In sentence 4, the correct use of an apostrophe is displayed by "country's" to indicate the possession of the top leader.

In sentence 6, the correct use of an apostrophe is shown by "school's" to convey that the homework club belongs to the school.

In sentence 7, the correct use of an apostrophe is seen in "boy's" to indicate ownership of the baseball by the boy.

In sentence 8, the correct use of an apostrophe is demonstrated by "days'" to show that the project was worth three days.

Please note that sentence 5, "It's time to buy new books for our classes next semester," also contains a correct use of an apostrophe. However, you did not choose it as one of the correct sentences.

The other sentences do not correctly use apostrophes:

1. "Canada's mens' hockey team wins gold medals almost every year." - The correct form would be "Canada's men's hockey team" to indicate that the team belongs to the men.

2. "Lets forget that we tried to build a racing car because it's been an awful experience for us and our friends." - The mistake here is the contraction "it's" which is a contraction of "it is." The correct form for possessive is "its," as in "it has been an awful experience."

9. "There are three pieces' of pie left." - The correct form should be "pieces of pie" without the apostrophe.

10. "We always have a big birthday party on my mothers birthday." - "Mother's" should be used instead of "mothers" to show that the birthday belongs to one mother.

Therefore, the five sentences that correctly use apostrophes are 3, 4, 6, 7, and 8.