You need Perspective effect for that
as Prkos has indicated this is what you will need, but you must do it a certain way.
1. Select the
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and type your text.
2. Then turn your text into a selection with the
3. Then in the Inkscape Menu (Path>Object to Path)
4. Click the
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and make your pespective shape. Beginning with the bottom left>top left>top right>bottom right>close the shape. (make sure no fill, but has a stroke)
5.With the
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select the perspective shape
first and then your text.
6. Menu: Effects>Modify Path>Perspective
7. Viola you have perspective text.
Oh what the heck if you are still having problems
this thread should clear everything up for you.