### Chinese: 注册证在有效期内是相应级别注册消防工程师的执业凭证，由注册消防工程师本人保管、使用。
### English: As the practice certificate of registered fire engineers of corresponding class within the validity, the registration certificate shall be kept and used by the registered fire engineer in person.
### Errors: There is a major error of incorrect translation is missing content from the correct translation at "As the practice certificate of registered fire engineers of corresponding class within the validity,". There is a major error of incorrect translation has stylistic problems at "the registration certificate shall be kept and used by the registered fire engineer in person.". There is a major error of incorrect translation includes information not present in the correct translation at "in person".

### Improved English: The registration certificate is the practicing certificate of the registered Fire Engineer of the corresponding level within the period of validity, which is kept and used by the registered Fire Engineer themselves.