Yes, it's perfectly correct.
"To those who are Irish, or of Irish descent, I wish all the best on St. Patrick's day!"
Yes, "To those who are Irish" is correct grammar. It is a prepositional phrase that correctly identifies a specific group of people.
No, "them guys" is not considered correct grammar. The correct phrasing would be "those guys".
No, the grammar is not correct. The correct way to say it is "You have to have it cleaned."
No, "Is was able to confirmed" is not correct grammar. The correct phrase would be "It was able to be confirmed."
No, it is not proper grammar. The correct phrasing is "you and I."
No, the correct grammar would be "Look at what you got."
Yes, that is correct grammar.
No, the grammar is not correct. The correct way to say it is "You have to have it cleaned."
No, "them guys" is not considered correct grammar. The correct phrasing would be "those guys".
Yes, "you were correct" is correct grammar. This sentence is in the past tense and conveys that someone was right about something.
This should say, The next stop will be somewhere in Vasayas, then it will be correct grammar. Written as it is it is not on correct grammar.
No, it is not correct
No, "Is was able to confirmed" is not correct grammar. The correct phrase would be "It was able to be confirmed."
No, it is not proper grammar. The correct phrasing is "you and I."
Yes
Absolutely.
No, The correct grammar for this sentence would be, "He finished doing his homework."
It is not correct to say "they has studied". The correct way is to say "they have studied." There are many different places that a person can check grammar questions such as English grammar websites.