We use formal greetings in serious situations or when we don't know people. We use informal greetings in friendly situations where we already know people. Let's take a look at some examples:

When we write letters and emails, we usually use formal greetings. Take a look at these examples:

When we are leaving people, we say goodbye to them. Like saying hello, there are different ways to do this:

When we write emails, just like saying hello, we should also say goodbye. Here are some common ways of doing that:

When you want to introduce yourself, you can use different expressions. For example:

There are times when we want to introduce someone we know to other people. There are different expressions that we can use in this situation. Take a look at these examples: