Pasting data from column selection

How do I paste the columnar data without adding lines, simply appending the data. For example, I select the quote from the x and y by holding the alt key then using the mouse to select:
"x",
"y",
z,
1,
2

HOw do I paste that onto z,1,2? When I do a simple paste, it add the copied data onto new lines pushing the z,1,2 down.

Thanks!