2. The phrase smooth operation in line 1 is closest in meaning to

　　(A) daily activity

　　(B) effective functioning

　　(C) delicate balance

　　(D) permanent location

　　3. According to the passage , carbon dioxide serves which of the following functions for fire ants?

　　(A) It protects the queen.

　　(B) It attracts other ant species.

　　(C) It informs workers of possible danger.

　　(D) It encourages the ants to gather together.

　　4. The word cluster in line 4 is closest in meaning to

　　(A) organ

　　(B) activity

　　(C) group

　　(D) cycle

　　5. According to the passage , each nest has a distinct odor that allows its inhabitants to

　　(A) find the location of the nest in the dark

　　(B) distinguish worker ants from other ants

　　(C) distinguish foreign ants from resident ants

　　(D) signal other inhabitants when foreign ants attack

　　6. The word alert in line 13 is closest in meaning to

　　(A) allow

　　(B) transport

　　(C) warn

　　(D) provide

　　7. What is the role of pheromones in the mass migrations of ants?

　　(A) Pheromones are used to create a trail that directs the ants during migrations.

　　(B) Pheromones signal the ants that the nest has been invaded and must be abandoned.

　　(C) Pheromones control the speed at which ants move from one location to another.

　　(D) Pheromones enable scouts to identify suitable areas for establishing a new nest.

　　8. The word scurrying in line 16 is closest in meaning to

　　(A) agreeing

　　(B) appearing

　　(C) competing

　　(D) rushing

　　9. The word others in line 21 refers to

　　(A) private messages

　　(B) species

　　(C) trails

　　(D) signals

　　10. Why does the author mention dead insects in line 23?

　　(A) To compare the social behaviors of ants with those of other insects

　　(B) To emphasize the dangers that all insects encounter

　　(C) To argue the superiority of ants over other insects

　　(D) To indicate a behavior that is common among various kinds of ants

　　11. Which of the following terms is defined in the passage ?

　　(A) pheromones (line 2)

　　(B) colony integrity (lines 12)

　　(C) mass migrations (line 14)

　　(D) private messages (lines 18-19)

　　PASSAGE 86 BBDCC CADBD A

　　最新热文推荐：

　　托福阅读真题原题+题目汇总

　　2020托福听力练习及文本下载汇总

　　托福考试：全国托福考点信息集锦