Learn More About Requesting and Responding to Interrogatories During the Discovery Process in Texas. (d) Certificate of Service.Certificate of Last Known Address. The server also needs to state in his affidavit the complete address of service for the defendant. This Note explains how to draft the case caption, introduction, instructions, definitions, interrogatories, signature block and certificate of service. Texas Rules of Civil Procedure 197 governs interrogatories. In general, Texas has very few official legal forms. This is why you will not always find a free fill-in-the-blank form for your situation. CV-Certificate of Service (Service of Papers Other than Citation). " fill in the blanks on (Mr.