Object is signed just like thing: form both hands as curved hands with thumbs sticking out, while the rest of the fingers are held together. Then held side by side in front of your body with both hands' fingertips facing each other, move the curved hands apart, gently bouncing sideways as they move further away from each other a couple of times.
Teach your toddler the object sign when they are ready to grasp the concept that many items around them can be classified as 'things' or 'objects', as opposed to living things: people, animals, and plants.
This is a useful flash card taught best in conjunction with objects that your toddler encounters or uses regularly.
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