Many under-educated parents find it hard to help their children with homework due to lack of formal schooling.

under-educated 是由前缀 under-（表示"不足、不够"）和形容词 educated（受过教育的）组成的复合形容词。under- 表示"低于标准"或"不足"，educated 表示"受过教育的"。 under-educated 合起来表示"受教育不足的"，指没有接受足够的教育或文化程度较低。