Announcement is something said, written, or printed to make known what has happened or (more often) what will happen.
In writing an announcement, keep the following points:
-The title / type of event.
-Date / time, place, and
-Contact person.
An announcement usually starts with an expression to get people’s attention, such as “Attention, please”. It is usually ended with an expression of thanking.
For Example :
This is an announcement text are (to write) in a school.