直接送达（direct service），是指公安司法机关指派法警将诉讼文书直接送交受送达人的行为。如果受送达人不在时，可以送交给与他共同居住的成年家属签收。如果受送达人委托诉讼代理人的，可以送交其代理人签收。如果受送达人已向人民法院指定代收人的，交代收人签收。根据法律规定，所有诉讼文书，均以直接送达为原则。

留置送达（service in lien），是指当受送达人或者他的同住成年家属无理拒绝接受诉讼文书时，送达人应当邀请有关基层组织的代表或者其他人到场，说明情况，并在送达回证上写明受送达人拒收的事实，送达的日期，由送达人、取证人签名或盖章，然后，把诉讼文书留在受送达人的处所，即视为送达。在民事诉讼的送达中，人民法院送达调解书时，不能采用留置送达的方式。

参考双语法规：

《民诉法》第七十八条：

送达诉讼文书，应当直接送交受送达人。受送达人是公民的，本人不在交他的同住成年家属签收；受送达人是法人或者其他组织的，应当由法人的法定代表人、其他组织的主要负责人或者该法人、组织负责收件的人签收；受送达人有诉讼代理人的，可以送交其代理人签收；受送达人已向人民法院指定代收人的，送交代收人签收。

Litigation documents shall be served directly on the recipient of the service. If the recipient of the service is a citizen, the documents may, in the case of his absence, be served on an adult member of the recipient’s family who lives with him. If the recipient of the service is a legal person or any other organization, the document shall be served on the legal representatives of the legal person, the principal leading personnel of any other organization, the personnel of the legal person or any other organization in charge of receiving such documents; If the recipient of the service has a litigation representative, the documents may be served on the litigation representative. If the recipient of the service has designated an agent to receive his litigation documents and has informed the people’s court of it, the documents may be served on the agent.

受送达人的同住成年家属，法人或者其他组织的负责收件的人，诉讼代理人或者代收人在送达回证上签收的日期为送达日期。

The date of receipt as signed by the adult family member living with the recipient of service, or persons in charge of receiving documents of the legal persons or other organizations, or litigation representative, or agents designated to receive his documents shall be regarded as the date the document is served.

《民诉法》第七十九条：

受送达人或者他的同住成年家属拒绝接收诉讼文书的，送达人应当邀请有关基层组织或者所在单位的代表到场，说明情况，在送达回证上记明拒收事由和日期，由送达人、见证人签名或者盖章，把诉讼文书留在受送达人的住所，即视为送达。

If the recipient of a service or any of his adult family members living with him refuses to accept a legal document, the person serving the document shall ask the representatives of the relevant basic organization or unit to which the recipient of the service belongs to appear on the scene, explain the situation to them, and record the reasons of the refusal and the date on the receipt. After the person serving the document and the witnesses have affixed their signatures or seals on the receipt, the document may be left at the place where the recipient of the service stays and the service shall be considered completed.

参考双语例句：

If an administrative licensing decision cannot not be served directly or by post by an accepting institution, it shall be served by public announcement.

第二十六条受理机构无法直接送达或者邮寄送达行政许可决定的，可以公告送达。

For direct service by an accepting institution, a receipt is necessary and the applicant shall date and sign or stamp on it.

受理机构直接送达的，必须有送达回证，由申请人在送达回证上记明收到日期、签名或者盖章。

Any notice, documents or materials, which for the purpose of performance of this contract, may be delivered by hand between parties hereto, and also by mail.

为履行本合同而需要发出的任何通知、文件或资料，双方可以互相直接送达，也可以通过邮寄送达。