1. Then I was a brigade liaison officer. After that,I finally became a battalion commander.
    然后我再当旅部联络官, 在那之后我终于当上营长.

2. Yes, I was a battalion commander when I got out of the army.
    是的, 我退伍时是营长.

3. I was a battalion commander when I got out of the army.
    我退伍时是营长.