Here are the designations for each sentence:

1. **S** - She is my aunt.
2. **S** - Thomas speaks Vietnamese fluently.
3. **C** - Mai and Hoa enjoy playing table tennis.
4. **C** - Linda sings and Peter plays the guitar.
5. **C** - Nga likes reading, so she bought a lot of books.
6. **C** - I went to Ha Noi and visited some temples and pagodas there.
7. **C** - She is a smart student, and she is an active member of our club.
8. **C** - Mary wants to join the school chess club; however, she can't play chess.
9. **C** - We go shopping, go to the cinema, and play sport together.
10. **C** - She has prepared everything for her performance, but she feels nervous.