1.

My sister

  used to

belong to a "chat group" on astronomy.

2.

People always

  used to

mail letters, but nowadays they fax them.

3.

A cellular phone

  is used to

make phone calls from cars or from the street.

4.

I

  used to

have a typewriter, but now I have a new computer.

5.

We just bought a new CD player. We     used to     have a cassette player,
but sound was terrible.

6.

Modems

  are used to

access the Internet.