Надо соединить в одно предложение!!!
1. Last year I went to Paris. I stayed there for a week.
2. I stayed with Louise. She is my French cousin.
3. She introduced me to Pierre. His knowledge of Paris is amazing.
4. My favorite building was the Invalides.

Last year I went to Paris where I stayed for a week. I stayed with Louise who is my French cousin. She introduced me to Pierre whose knowledge of Paris was amazing.