Based on my experience, I'll advise that you read your I140 petition to be familiar with your proposed endeavor and why you're well suited to achieve it. Also, you and your spouse should be able to answer questions about each other and have other proof of marriage (you can use the documents listed in your interview invite as a guide).

I am surprised that people with employment based petition also get interviewed. I though they don’t interview these kind of applicants.

See the questions I was asked. I also had H-1B visa and I am the principal applicant. What do you do you? When did you come into the USA? How long have you been married? Where did you meet your spouse? What degree did you get for the job you do? Where is the location of your current employer? How old is my son. To my Spouse What do you do for a living? Current employer’s address ? Have ever been married before? She made me and my husband sign on a sheet of paper after we each answered our questions. Overall it was a very good experience, the interview process went smoothly and the IO was friendly.

@Ishhhh Oh , thanks for the information.

@KY KY , that’s what i thought as well, I assumed they will approved my case initially after they cancel my interview last 2 weeks ago but it turns out it’s just a reschedule

@K I-485 , This is a very detailed information, I will put this as a note and will share it to my wife as well. Thank You

following

@K I-485 thank you for sharing this!

@K I-485 Great info! Thanks