Answer: 1. Underline "pony" and "its" (the its right before halter)
2. Underline "Mr.Chisholm" and "his"
3. Underline "flowers" and "they"
Explanation: Basically you underline the noun in the sentence (person, place, thing, idea), and also underline whatever pronoun used for said person, place, thing, or idea. Just read the actual word sentences a bit and you'll make it through! Good Luck :]