I hope this letter finds you well. I wanted to write to you about something important. As you know, your birthday is just around the corner, and I couldn't be more excited for you! I've been looking forward to celebrating this special day with you for weeks. However, due to unforeseen circumstances, I won't be able to attend your birthday party. I want you to know that it truly saddens me to miss out on all the fun and laughter that I'm sure will fill the air. Please know that even though I can't be there in person, my thoughts will be with you as you celebrate another wonderful year of life.

Warmest regards, Johnny.

1. What does the writer mean by "unforeseen circumstances"?

2. Why does the writer express excitement about the birthday party?

3. How does the writer express their regret for not being able to attend the party?

4. Why does the writer reassure the friend that their thoughts will be with them?

5. What is the tone of the letter?