Combine these sentences by using relative pronouns

COMBINE THESE SENTENCES BY USING RELATIVE PRONOUNS
1) This lady looks very tired. She has just returned from a long trip
2) We have bought a house. It is near the beach
3) Have you seen my dog? I have just left it here
4)This is the city. I used to live there three years ago
5) Minh is very sad now. His English marks are very low
6)The train isn't running today. It goes to Oxford