One of four new ``Let's Explore'' board books, with unusually clear, cheery, well-designed illustrations and suggestions for activities or interaction. Here, the title is repeated for each spread: ``...like a dog. WOOF ...like a truck. BRMM, BRMM.'' In Let's Do It, different children respond to questions like, ``Can you bite your toes?'' ``Can you play peek- a-boo?''—each highlighting a part of the body. Both books would be appropriate for toddler groups. The other titles, Let's Try and Let's Play, which suggest doing things with toys or around the house—``Can you knock down the blocks?''; ``Let's try to drink the milk''—are not quite as strong but still above average for the genre. (Picture book. 0-4)