5 Choose the correct option.
1 We went skiing in / on the mountains last year.
2 We saw some black cows on / in a big field.
3 My uncle has a house by / on a lake.
4 My parents would like to live in / on the coast so
they can look at the sea every day.
5 My friend lives in / on an. island and has to take a
boat to go to school every morning.
6 We can walk along this path and then have a picnic
by / in the river.​