To sign farm, take your open dominant hand, and start with your thumb touching your non-dominant side. Then trace the jaw all the way around to your dominant side.
If your baby is interested in animals, farm is a good sign for teaching them to group all the domesticated farm animals, like cow, sheep, and pig.
You can teach this sign when visiting a rural area, during story time, or if your baby happens to live on a working farm.
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