Emailing a friend back about weekend plans
Informal
Asking your teacher about your homework
Formal
Applying for a job advertised online
Formal
Asking your boss for a day off
Formal
Confirming a lunch date with your friend.
Informal
Sending a thank-you note to a friend
Informal
Sending Christmas wishes to your customers
Formal
Confirming your attendance at a training session
Formal
Writing to a customer service department about a faulty product
Formal
Inviting your neighbours to a BBQ party at your home.
Informal
Answering your friend's email
Informal
Emailing your cousin about your last holidays
Informal