题目内容：
In families with two working parents, fathers may have more impact on a child's language development than mothers, a new study suggests.
Researchers __1__ 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, __2__ all of their speech. The study will appear in the November issue of The Journal of Applied Development of Psychology.
The scientists measured the __3__ number of utterances (话语) of the parents, the number of diffe-rent words they used, the complexity of their sentences and other __4__ 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 __5__ 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 __6__ of child care and the number of different words the father used.
The researchers are __7__ why the father's speech, and not the mother's, had an effect.
"It's well __8__ 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 __9__ had a strong influence on their children's speech development, Ms. Pancsofar said, "or it may be that mothers are __10__ 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
1
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