1 . The complexities of human relations are difficult enough for adults to identify — and they have at least some idea of the rules. Children have yet to learn those rules. Infants are, nevertheless, able quickly to identify close relationships between other people, and thus to build up a map of the social world around them.
How this comes out has puzzled sociologists for decades. In a paper just published in Science, Ashley Thomas of the Massachusetts Institute of Technology proposes a partial answer: saliva (唾液) shared by kissing, for example, or the common use of an eating or drinking tool.
The researchers came to the conclusion based on a series of studies. To study those questions, the researchers observed toddlers (16.5 to 18.5 months) and babies (8.5 to 10 months) as they watched a video to see interactions between human actors and puppets (木偶). In the experiment, a puppet shared an orange with one actor, which indicates involvement of sharing saliva, and then threw a ball back and forth with a different actor. The researchers observed the children’s reactions when the puppet showed distress while sitting between the two actors. The team found that the infants were more likely to look toward the actor who had shared food with the puppet, not the one who had shared a toy, when the puppet was in distress.
Conducting her experiment by video enabled Dr. Thomas to cast her search for trial participants beyond Massachusetts. She nevertheless decided, in this first instance, to limit things to the United States. Future runs, she hopes, will reach beyond that country’s borders.
1. What does the underlined word “this” in paragraph 2 refer to?
| A．Adult’s identifying human relations. |
| B．Children’s learning interpersonal rules. |
| C．Babies’ getting to know new things around them. |
| D．Infants’ recognizing relationships between people. |
2. Which can best describe the research process?
| A．Well-designed. | B．Time-consuming. |
| C．Tightly-scheduled. | D．Risk-taking. |
3. What can the tests illustrate?
| A．Infants tend to believe in adults blindly. |
| B．Saliva sharing is indicative of closeness. |
| C．Infants are competent to show sympathy. |
| D．Saliva sharing acts as a comfort for infants. |
4. What was Dr. Thomas’s expectation for the future tests?
| A．An extension of age group. | B．More advanced equipment. |
| C．A broader regional coverage. | D．Diverse experimental methods. |
