1. U19 不定代名詞 one 和 ones

2. 不定代名詞用來取代前句提過的同類名詞 但並非同一個  I bought a red car, but my friend bought a black car.= I bought a red car, but my friend bought a black one. 若指的是同個名詞 則單數用 it 複數則用 them  I like your watch, and I want to buy one.  I like your watch. Can I buy it from you?

3. one 取代前面提過的單數可數 N, ones 取代 前面提過的複數可數 N  The pencil is too short. I need a long one.  The shoes are too small. I want big ones.  I don’t like the shirt. I want that one.

4. 1. A: Have you ever seen a koala before? 2. B: Yes, I saw (it, one) two years ago. 3. I like blue dresses, but my sister likes pink (them, ones). 4. Marvin and Kevin like to talk in class. I don’t like (them, ones). 5. Coffee cookies are delicious, but durian (them, ones) are terrible! 6. I can’t solve this problem. Can you solve (it, one) for me? 7. Maria missed the 7:00 flight. She had to take the 8:00 (it, one).

5. The pencil is too short. (longer) Please give me ______________. This bag is pink. (blue) I want ___________. The person is too weak. (strong) I need ____________ to carry this heavy box. These computers are slow. (fast) The boss needs _________ in his office. I didn’t buy these shoes. (those) I bought ________. Red hats are cheap. (green) ___________ are expensive. a longer one a blue one a stronger one fast ones those ones Green ones