Teach the opposites of inside and outside together, as the contrast between the two words helps illuminate the meaning for your baby. You can practice by making a game of stepping inside and outside the doorway as you do each sign.
Teach the signs for inside and outside together as a pair. The opposite meanings of the two signs helps your baby catch on to the meaning. To teach the signs you can go inside and outside the house, or put a toy inside and outside their toy house.
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