Поставьте прилагательные в сравнительной или превосходной степени. 1. Strength of materials is (difficult) than chemistry. 2. This metal is (brittle) than iron. 3. The University is one of the (tall) buildings in Moscow. 4. Copper is (hard) and (strong) than aluminium. 5. Is it (interesting) to study at university than at school? 6. Steel is (heavy) than (aluminum) and (flexible) than steel. 7. What is (expensive) material in the world? 8. The new transistor is (powerful) than the old one. 9. Metal is (strong) than plastic. 10. Nitrogen is (abundant) gas in the atmosphere.

1 more difficult 
2 brittler
3 tallest
4 harder stringer
5 more interesting
6 heavier more flexible
7 the most expensive
8 more powerful 
9 stronger
10 the most abundant