Помогите пж

1 The house is in/at the shape of a seashell.
2 There are posters on/in the walls.
3 You can't walk in/at space.
4 There are small huts in/on the island.
5 The flat is at/on the third floor.
6 We're excited for/about our new house.
7 The place is popular with/for tourists.
8 The island is home for/to twenty families.