地道的表达应该是 This is to certify (或declare,state,evidence) 或 we hereby certify!
举例：
CET-6大学英语考试六级证书Certificate of College English TestThis is to certify that ___________, a student of Grade ______ at Department of __________, ___________ University/Institute, passed the examination of College English Test Band-6 （CET-6）in January/June XXXX. Upon examination, he/she has fulfilled the band 6 requirements College English Syllabus Band Six with excellent/qualified score and is hereby awarded the Certificate of CET-6.
Department of Higher Education
State Education Commission （国家教委）
或
Ministry of Education （教育部）Date of Issuance: Certificate No.:
this is to certify that
Hereby certify
这两条都可以
在中文中,一般是先写所证明之事，然后在最后面另起一段，加上“特此证明”。或者是在开头就写“兹证明。。。。”
在英文中，通常在开头就直接写“This is to certify that .....”或“It is hereby certified that......”,即为“特此证明”之意。（注：这两种写法都很常见。）
例文：
张旭
Letter of Certification To whom it may concern: This is to certify that AAA Co., Ltd (hereinafter called “A”) has established partnerships with BBB Company (hereinafter called “B”) regarding of the highway construction, railway construction, bridge engineering, rail transit, airport, ports and wharves etc. As the agent of A in C country, B company will provide construction materials, equipment and resources etc. for A. Hereby certified! Tel: ************* Fax: ************* E-mail: ************* http: ************* ADD: ************* Certifier: A Date: October 10th, 2012
特此证明
IN WITNESS WHEREOF
供参考
特此证明
hereby to certify
我们所填写的资料准确无误，健康状况适合参加比赛，特此证明。
We certify that the particulars are correct and we are physically fit to participate in the event.
特此证明 hereby to certify;
[例句]我特此证明：本表所填写的内容和提供的材料真实无误。
I hereby certify that: All the information on this form is true and correct.
特此声明英语可以说成(hereby certify),一般用在文本后面了:)~
比较地道的说法,常用的如某某公司的特此声明We hereby certify that...
如实例:)~
(我方)特此声明上述所提供全部属实!
We hereby certify that the information disclosed herein is true and correct.
:)~