Fill in prepositions where necessary to complete the sentences.

1)People have always studied living things... their natural environment.
2)How does our environment influence... our children?
3)I don't think people living ... isolation could be happy.
4)Ecologists study what happens ... different species of birds and animals.
5)My father's influence ... me was great.
6)My interest lies ... nature .I am fond ... animals.
7)It's not easy it collect information ... this species of plants.
8)Mr Brown is 92 years old but he is ... good health.
9)What's the number ... children in your family?
10)Ecology is a science ... our environment.