In families with two working parents, fathers may have more impact on a child’s language development than mothers, a new study suggests.

Researchers 【S1】______ 92 families from 11 child care centers before their children were a year old, interviewing each to establish income, level of education and child care arrangements. Overall, it was a group of well-educated middle-class families, with married parents both living in the home.

When the children were 2, researchers videotaped them at home in free-play sessions with both parents, 【S2】______ all of their speech. The study will appear in the November issue of The Journal of Applied Developmental Psychology.

The scientists measured the 【S3】______ number of utterances(话语) of the parents, the number of different words they used, the complexity of their sentences and other 【S4】______ of their speech. On average, fathers spoke less than mothers did, but they did not differ in the length of utterances or proportion of questions asked.

Finally, the researchers 【S5】______ the children’s speech at age 3, using a standardized language test. The only predictors of high scores on the test were the mother’s level of education, the 【S6】______ of child care and the number of different words the father used.

The researchers are 【S7】______ why the father’s speech, and not the mother’s, had an effect.

“It’s well 【S8】______ that the mother’s language does have an impact”, said Nadya Pancsofar, the lead author of the study. It could be that the high-functioning mothers in the study had 【S9】______ had a strong influence on their children’s speech development, Ms. Pancsofar said, “ or it may be that mothers are 【S10】______ in a way we didn’t measure in the study”.

A) already B) analyzed C) aspects D) characters

E) contributing F) describing G) established H) quality

I) quoted J)recording K)recruited L) total

M)unconscious N)unsure O) yet

【S7】