tending universities at an older age\r10) the marriage of some undergraduates will inevitably\rU nit 10\rP 146 Understanding Short Conversations\r1 .A 2 . B 3. B 4. C 5. D 6 .A 7 . B 8. D 9. C 10. D\rP 148 Understanding Long Conversations\rl.B 2. D 3 .C 4 .A 5 . C\rP 149 Understanding a P assage\r1 .A 2 .C 3 . B 4. D 5.A\rSupplementary Listening\rP 156\rTask 1\r1 .C 2 .A 3 . B 4. D 5. B\rP 157\rTask 2\r1 .D 2 .A 3 .A 4 . D 5. B\rP 142\rTask 3\r1) organisms 2) untreated 3) occurrences 4) agriculture 5) encouraged\r6) administrations 7) attributed 8) Some things have been done to address this problem\r9) in an effort to raise the public's awareness of environmental protection\r10) to punish enterprises that drain untreated wastes into the rivers and the oceans