17. Olga is a good student. She's _____ student in the school.
A. the best
B. better
C. gooder
D. the goodest
18._____have two wings and lay eggs.
A. Mammals
B. Birds
C. Reptiles
D. Amphibians
19._____don't have lungs when they are young.
A. Mammals
B. Amphibians
C. Birds
D. Fish
20.______are cold – blooded.
A.Mammals and birds.
B. Fish and Mammals
C. Fish and reptiles
D. Birds

21._____have 4 legs.
A. Adult mammals
B. Adult reptiles
C. Adult birds
D. Adult amphibians
23. Sharks, whales and dolphins
gills. They have lungs instead.
B. have got
C. haven't got
D. don't grow
D. grow
24 _______can a crocodile grow? – It can grow to about 4 metres.
A. How long
B. How far
C. How big
D. How tall
25._________can a giraffe grow? - It can grow to between 5 and 6 metres.
A. How tall
B. How long
C. How far
D. How big