be covered by/with有什么区别?怎么用?

1)be covered by ... : 由...承担/负担/支付;被...掩护/报道/监视/控制等等,表示抽象的概念, 后面接人, 机构, 或者组织. These expenses are covered by the state. 这些费用都由国家负担。 All road out of town has been covered by the police . 所有出城的道路