How to ensure two Gridviews pair together horizontally ?

I have 2 Gridviews and I must have them arrange horizontally meaning one on left and the other one must be right adjacent to the right.
However, even I stick the code together they still go one at the bottom of another.
Any way to do it together horizontally ?
I guess the way is to use Table of 1 row two column ?
But the problem is these 2 Gridviews will always have same row that's fine but their number of columns and width keeps changing according to the query so we cannot hardcode the width of the tables.
What can I do ? Pls help. Thanks
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