4.(61)Itis reported that the parents'teaching style has an effect on the relationship between the children and their parents.Teens(62)whoseparents establish house rules have better relationships with their parents and a(63)lower(low) risk of smoking,drinking,and using drugs(64)thanother teens,according to a study conducted by (65)theNational Center On Addiction and Substance Abuse. The study,which analyzed a hands-on and hands-off approach,found that teens(66)living(live) in hands-on environments have parents who monitor their children's TV and Internet use,know and restrict the CDs they buy,know (67)wheretheir teens are after school and on weekends,eat dinner with their teens six(68)orseven nights a week and assign the chores. What's more,the survey(69)found(find) that 57 percent of teens have better relationship with hands-on parents.Only 24 percent of teens with hands-off parents reported an excellent relationship with(70)theirmothers and only 13percent said they had an excellent relationship with their fathers.
5.Before the lecture,the young scientistput forward such an abstract concept(提出如此抽象的一個概念) that everyone kept silent digesting the meaning but it might take a long time for them to truly master it.