North Americans send cards for many occasions. They send cards to family and friends on birthdays and holidays. They also send thank-you cards, get well cards, graduation cards, and congratulation cards. It is very common to buy cards in stores and send them through the mail, but turning on the computer and sending cards over the Internet is also popular
a) Sending cards is very popular in North America.
b) Birthday cards are the most popular kind of card.
c) It is important to send thank-you cards.