1, You can write the message at the back

2, Many people send portcards when they are on holiday because portcards are cheap and the pictures on them are often better than people’s  on photos

3, Someone send the first portcard at the end of the nineteenth century 

4, People in rhe past like to see the portcards because they didn’t have pictures in their newspaper then

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1. These postcards often have  pictures of beaches, mountains or ccastles on them and you can write a message at the back.
2. Because postcards are cheap and the pictures on them are often better than people's own photos.
3. Somebody sent the first postcard at the end of the nineteenth century.
4. Because they didn't have pictures in their newspaper then.