81. Today the tide of HIV infection ____.

1. drowns 14 000 people
2. calls for a cheap, effective vaccine
3. rolls without any countervailing measures
4. is curbed with an inexpensive, effective vaccine

82. Neither of the vaccines tested in the two large-scale trials ____.

1. is in a right track
2. turned out to be a manufacturer
3. is sufficiently funded for research
4. is capable of inhibiting the tide of HIV infections

83. The author questions ____.

1. the two rivals' intention to back down
2. insufficient investment in AIDS research
3. the two trials testing almost identical vaccines
4. the allocation of funds between the NIH and the DoD

84. According to the passage, it is imperative that ____.

1. the two rivals of AIDS vaccines change their research lines
2. less pressure be imposed upon the NIH and the DoD
3. the NIH join the DoD
4. all of the above

85. The strategy put forward in the passage implies that ____.

1. rivalries can hamper the fight against AIDS
2. there are no shortcuts to conquest over AIDS
3. the tide of AIDS infections is not taken seriously enough
4. one single institution is enough to turn out an effective vaccine

(Reference keys.)