I wpuld like to put together two photos into one.
I will appreciate your help.
That is not, at present, a feature of iPhoto.
You can create slideshows, books, cards, etc. which allow you to arrange multiple photos together, but iPhoto does not allow you to combine separate images.
After posting my question, I googled "how to make a collage" and found several resources from an app available in iTunes App Store and instructions using Pages.
If you have iWork Pages can be used to do what you want.
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