UNIT 1: 33-50

3. sea creatures that live in shells and are eaten as food, or one of these creatures
5. feeling weak or ill and unable to think clearly
9. a transparent, usually bright blue, precious stone
10. the hard shell of a turtle
11. a public transport vehicle
13. the second sign of the zodiac
14. any of six children born to the same mother at the same time
16. morally correct
17. a dangerous fish which lives in South American rivers, has sharp teeth and eats meat
18. Someone who is thick-skinned does not appear to be easily hurt by criticism

1. a tower built especially around the edges of prisons and army camps
2. a type of bacteria that exists in several forms, some of which live in food and make the people who eat it ill
4. a woman's shoe with a narrow high heel
6. without any words
7. Japanese mustard
8. chimes an arrangement of shells or small decorative shapes of metal or wood that make a gentle noise when moved by the wind
12. a small musical instrument, consisting of a circular wooden frame
15. the choice of words used to express something