Dragging or pasting within TextEdit behaves weirdly. Help!

Question

I'm working in TextEdit and I want to move some text within the document. First I try the cut & paste method—but the text on the clipboard won't paste where I've placed the cursor; it puts the text ABOVE the sentence or paragraph or section. Then I try a different method, dragging the highlighted text to the spot I want to move it to, and the same thing happens; the text snaps up to the top, above the line or paragraph that I'm working on.
It's the weirdest thing, and I can't figure out what's causing it. It makes editing a nightmare, impossible even. Any clues.
Thanks!

Answer 1

Not weird at all.  When you select entire lines you also select the newline character (end of line character) at the end of the lines, including the last line of the selection. Here's an example.
In the first picture I selected the first three lines.
And in the following I selected the first three lines not including the newline character at the end of the third line.
Note the difference in the highlighting.
In the first case the newline is selected so it will cause that entire selection, including that ending newling to be placed at the insert point.  Thus the selection will appear on the line before the insert point (or break a line if the insert point is not at the start of a line).
In the second case the ending newline is not selected and thus the final line would appear immediately in front of, and on the same line as the insert point.
So if you happened to select entire lines as in the first case, then backspace over the final newline of the insertion if you didn't intend to include it.