There are no fixed expressions for the beginning and ends of meals. Some religious people say a short prayer before and after meals. It is common for guests and family members to say something complimentary about the food during the deal (for example This is very nice). After the meal you can say: That was lovely/delicious; thank you very much.

Drinking

When people begin drinking alcoholic drinks socially, they often raise their glasses and say something. Common expressions are Cheers! (GB) and Your health!

When we drink to celebrate an occasion (a birthday, a promotion or a wedding), we often say Here’s to …!

Here is to Alice!
Here is to the new job!
Here is to the happy couple!

Thank-you notes

Thank-you notes express thanks. Because they have a specific purpose, thank-you notes have to be organized more carefully than personal letters. Follow these guidelines when you write a thank-you note:

Mention the specific gift or act of kindness.
Explain why the gift or kindness was appreciated. Be as specific as possible.
Send the letter promptly, since this can help avoid misunderstandings, as well as show your appreciation.
What happens if you didn’t like the gift? No matter how stinky the gift, it still deserves acknowledgment. Don’t lie and gush about the gift. Instead, be polite and more general in your thanks.