can 和 must 用于被动句其结构分别是什么，请举例说明！
can 和 must 作为情态动词，它本身不可以用于被动语态，但它们后面所接动词可以用被动式。如：
▲can后接动词的被动式
No rules of universal application can be given. 订不出常见适用的规则。
They can be trusted to some degree. 从某种程度上说他们是值得信赖的。
In given conditions a bad thing can be turned into a good one. 在肯定条件下，坏事可以变为好事。
In meetings she always takes the offensive before she can be criticized. 在会上，她一直不等其他人批评她就先发制人。
A man’s character can be measured by the types of men with whom he associates. 一个人的品格可按与他结交者的种类来衡量。
This dictionary gives the meanings of words and also illustrates the constructions they can be used in. 本词典提供词义讲解，并举例说明遣词造句的办法。
▲must后接动词的被动式
Glass must be treated carefully. 玻璃需要小心用。
Children must be accompanied by an adult. 孩子须由成人陪同。
These chemicals must be tightly kept. 这类化学药品须密封保存。
Debts of blood must be paid in blood. 血债要用血来偿。
Application must be made this afternoon. 申请需要在今天下午提出。
The work must be done within the given time. 工作需要在规定时间内完成。
The job must be done exactly as she wants it done. 这件工作需要准确地根据她的需要做。
