6. Choose the correct answer. Не ... the text before I decided to help him.
a) translated
b) had translated
c) has translated
d) will translate
8. Answer the questions.
What is the difference between cartilage and bone?
a) Cartilage is rubbery, and bone is firm.
b) Bone is rubbery, and cartilage is firm.
c) Bone is more primitive tissue than cartilage.
d) Bone is inside the body, and cartilage is outside.

9. Answer the questions.
What is the organ that pumps blood all throughout the human body?
a) The heart
b)The lungs
c) The kidneys
d) The blood vessels and capillaries

10. Answer the questions.
Why does blood turn dark red as it circulates through the body?
a) It starts to clot
b) The oxygen in it is replaced with carbon dioxide
c) It gets old and dirty flowing through the body
d) The farther blood is from the heart, the more dark red it is

11. Answer the questions.
What is the function of the blood vessels and capillaries?
a) They pump blood to the heart
b) They filter impurities from the blood
c) They carry blood to all parts of the body
d) They carry messages from the brain to the muscles

12. Answer the questions.
What happens to blood when it is pumped into the thin-walled blood vessels of the lungs?
a) Carbon dioxide is replaced with oxygen
b) Platelets are exchanged for plasma
c) Blood fills the lungs and causes coughing
d) Nothing- the lungs are just a place blood goes through on its way back to the heart

13. Choose true variant.
... you ... my English book anywhere? I can find it nowhere.
a) Did ... see
b) Will ... see
c) Had ... seen
d) Have ... seen

14. Choose true variant.
English is the world language and it is the language in the USA or Australia differs from the English language spoken in Britain.
a) spoke
b) spoking
c) spoken
d) have spoken

17. Answer the questions.
What is the difference between compact bone and spongy bone?
a) They have different bone marrow.
b) They are made of different materials.
c) They have different sizes of bone cells.
d) They have different arrangement of bone cells.