This is my original sentence:
1A) Babies will reach out for toys when sitting, point at small items with their index finger, and use their index finger, middle fingers and thumb to form a pincer grip to pick up items and hold them in their hand.
I looked over it and I realised that I’m referring to babies therefore the body parts must be plural. So I changed it to:
1B) Babies will reach out for toys when sitting, point at small items with their index fingers, and use their index fingers, middle fingers and thumbs to form a pincer grip to pick up items and hold them in their hands.
Is this sentence grammatically correct? Can I write it like this or does it sound odd?
If it is fine, would I have to change feet to feets and hand to hands in these two sentences?
2) They will ride a tricycle by pushing along with their feets.
3) They will have progressed to drawing circles, lines, and dots using their preferred hands.