听力文本：

In an email program, the inbox is usually the main screen.
On your desk, it's probably a small box that other people put papers into.
I check my inboxes, meaning that I look to see if there is anything inside them.
First, I go to the mailroom. A "mailroom" is a room in a large office building where mail is organized so that it can be given to the right person.
Offices with many employees might receive thousands of pieces of mail, so they need to have special employees who work in the mailroom and make sure that each piece of mail gets to the right person.
You may start out in a company by working in the mailroom, which is usually considered the lowest level job in a company.
Some people think that if you work hard enough, you can start in the mailroom and someday be president, although I don't think that happens very often in most companies!
When I'm in the mailroom, I check my mail slot to see what mail has arrived overnight.
A "slot" is normally a small rectangular opening in something, but a "mail slot" is a small box that has a person's name on it and holds mail for that person.
Some houses have mail slots in their front doors.
I live in an older house, where we still have a mail slot in our door; many houses now, however, have "mailboxes," these are little boxes outside of your house.
In the story, I'm talking about the mail slots in the mailroom in the office building where I work.
There are always a lot of intra-office and inter-office letters in my mail slot.
An "intra- (intra-) office letter" is one that is sent and received within one office building.
An "inter- (inter-) office letter" is one that is sent between different offices of the same company.
For example, if I work at a large bank and I want to send something to a customer, I put it in the regular mail.