Many parts of the plan will fully take effect in four years. But some take effect quickly. For example, in six months the new law will bar insurance companies from denying coverage to children with pre-existing health conditions. Adults with pre-existing conditions will be added in four years.

四年之內(nèi)，該計劃的許多部分都將全面生效。但是其中一些措施將很快生效。例如，六個月之內(nèi)，新的法律將禁止保險公司拒絕為存在先天性疾病的兒童進行賠付。四年之內(nèi)，患有先天性疾病的成年人也將納入償付范圍。

Bar: to forbid or prevent somebody from doing something 禁止;阻止

The players are barred from drinking alcohol the night before a match. 運動員在參賽前夜不得喝酒.