Directions： Read the following text. Choose the best word（s） for each numbered blank and mark A， B， C or D on ANSWER SHEET 1. （10 points）
Many theories concerning the causes of juvenile delinquency （crimes committed by young people） focus either on the individual or on society as the major contributing influence. Theories （21） ____ on the individual suggest that children engage in criminal behavior （22） ____ they were not sufficiently penalized for previous misdeeds or that they have learned criminal behavior through （23） ____ with others. Theories focusing on the role of society that children commit crimes in （24） ____ to their failure to rise above their socioeconomic status （25） ____ as a rejection of middle-class values.
Most theories of juvenile delinquency have focused on children from disadvantaged families， （26） ____ the fact that children from wealthy homes also commit crimes. The latter may commit crimes （27） ____ lack of adequate parental control. All theories， however， are tentative and are （28） ____ to criticism.
Changes in the social structure may indirectly （29） ____ juvenile crime rates. For example， changes in the economy that （30） ____ to fewer job opportunities for youth and rising unemployment （31） ____ make gainful employment increasingly difficult to obtain. The resulting discontent may in （32） ____ lead more youths into criminal behavior.
Families have also （33） ____ changes these years. More families consist of one parent households or two working parents； （34） ____， children are likely to have less supervision at home （35） ____ was common in the traditional family （36） ____. This lack of parental supervision is thought to be an influence on juvenile crime rates.
Other （37） ____ causes of offensive acts include frustration or failure in school， the increased （38） ____ of drugs and alcohol， and the growing （39） ____ of child abuse and child neglect. All these conditions tend to increase the probability of a child committing a criminal act， （40） ____ a direct causal relationship has not yet been established.