Fill in the blank space with the correct aform of the words in the par

entheses :

1/ He is going to .....coins.He hopes he'll have a lot of types coins ( collection )

2/ She eats a lot of junk , but junk food causes.....(obese)

3/ A hobby is an ......that you do for pleasure ( act )

4/ I'm ........to shellfish , so I can't eat lobster and shrimp ( allergy )