He didn't contribute to the meeting until the end. Only at _________________________________.
Only at the end did he contribute to the meeting. / Only at the end of the meeting he contributed.
She didn't even answer my main question. My _________________________________.
My main question she didn't even answer / wasn't even answered.
I like her as a person, but I can't stand her lack of profesionalism. It's _________________________________.
It's her lack of professionalism I can't stand.