It is a simple sentence.
A simple sentence contains one independent clause - which is the case with sentence 7. There is one subject (they) and one verb (rule), which means that it is a simple sentence (because of one verb only). A dependent clause wouldn't be able to stand on its own, and sentence 7 obviously can, which is why it is not dependent.
A character who conquers a scary creature.
Answer:
1. Thomas CLEANS his teeth every day. a) is cleaning b) clean c) cleans 2.
2. Georgia IS WEARING her new trousers today. a) is wearing b) wears c) are wearing
3. I DON'T GO to the library every week. a) am going b) don't go c) am not going
4. Rosa and Elena WRITE to their grandmother every week. a) write b) are writing c) is writing
5. Andreas and Jim DON'T MAKE their beds every day. a) making b) aren't making c) don't make
6 I AM NOT WEARING my glasses at the moment. a) wear b) am not wearing c) don't wear
7. We ARE HAVING our breakfast now. a) have b) having c) are having
8. Thomas usually PLAYS the guitar but now he IS PLAYING the piano. a) plays / playing b) play / is playing c) plays / is playing
9 Katya IS GOING swimming now. a) goes b) go c) is going
10 My friends ARE RUNNING in the park currently. a) are running playing b) are running c) is running