Kids from different economic backgrounds behave ___56._____ in classrooms. For example, working-class kids are ___57._____likely to ask for help from teachers than their middle-class counterparts. And when/if they do ask for help, they’re less aggressive about it.
That’s according to a study that followed students from the third grade through the fifth, ___59._____ in the journal American Sociological Review. Part of the difference in how kids act ___60.____ from the guidance they’ve gotten at home. As ___61.____ rule, working class parents coach their kids to work out problems on their own. And if the kids did ask for help, it was in subtle ways—like sitting quietly____62.____a hand raised. Middle class kids? Their parents urged _________ to be proactive, even to interrupt their teachers for help.
The result is that teachers were more likely to attend to the assistance-seekers and louder class-participators,_____64.____ left working class kids behind and magnified inequalities.
请问这里是用 when 最好，还是if 最好。
1. For example, working-class kids are more likely to ask for help from teachers than their middle-class counterparts. And when they do ask for help, theyre less aggressive about it.
2. For example, working-class kids are more likely to ask for help from teachers than their middle-class counterparts. And if they do ask for help, theyre less aggressive about it.
选择when 正确。
选择if 的缺点：
1. if 仅表示一种假设，未必大家肯定那样去做，给人一种不肯定发生的感觉。
2. if 引导的条件句，毕竟是一种假设，不肯定真的去做，所以极少用do + 动词原形表示强调。
