Variant 1 You could have come first and won the race if you … faster

21. According to the passage; one can conclude that ...

A) it's certainly dangerous to blow up ones’ house

B) someone not doing well at school means that he is dull

C) getting into trouble meant cool for Thomas Edison's classmates.

D) children, thirsty for knowledge, often cause considerable inconveniences.

22. According to the passage, the phrase BECAME ACCUSTOMED TO is opposite in meaning, to ...

A) were in the habit of B) it was usual for C) got used to D) it was strange for

Birds are warm-blooded animals with feathers and wings. Unlike mammals, birds lay eggs. Feathers provide insulation for birds, allowing them to maintain a high body temperature. Their long wing feathers help them get the lift necessary for flight. Birds fly pretty fast. They can fly even faster in case of emergency. Ducks have been known to fly more than 60 miles per hour when being chased. Not all birds can fly, however. The largest of all living birds, the ostrich, cannot fly.

There are more than 9,000 species of birds. They can be found in just about every type of environment. Among the best known are the birds of prey such as hawks, eagles, and owls. More than half of all birds are perching birds. They have an arrangement of toes and leg tendons that let them balance like an acrobat an small twigs or telephone wires. Songbirds make up most of this group, which includes sparrows, finches, crows, blackbirds, thrushes, and swallows. Aquatic birds get most of their food from water. Some of these birds, such as the albatross, spend much of their time over the open ocean. Others, like penguins, live on the land.