3. Researchers have found a strong association between computer and Internet us
adolescents and engagement in multiple-risk behaviours (MRB), including illicit drug
use, drunkenness and unprotected sex.

4. Drug resistance remains a major problem in combating HIV infection, but a different
approach to drug development could be the answer.
5. North China's Shanxi Province, the country's largest coal supplier and most polluted
region, has the dubious distinction of having 16 cities on the list. Neither Beijing nor
Shanghai appear on the list. The report found that only 22.94 percent of sewage was
treated adequately in the cities surveyed and less than 20 percent of household garbage
met with proper handling. It said 178 cities examined had not built any sewage treatment
facilities and 130 cities had not been equipped with garbage disposal plants. CAN ANYBODY PLEASE PARAPHRASE THESE SENTENCES