Расставьте :
ответы : to recycle
ecology
a volunteer
a nesting box
to clean out
rubbish

Верхним слова нужно вставить :

to make free from dirt and rubbish

a box for birds to best in

things of no use that are thrown away

a person who does services without payment or reward

to treat smth that has already been used so that it is fit to use again

the relation of plants and living beings to each other and to the environment