Question: cut/paste between worksheets

Hi:

I have a worksheet with a fairly complicated expression. Suppose it is of the form A:=B.

In red I have

>A:=B;

and just below it, in blue I have

A:=B

Now I highlight the blue "A:=B", press CTRL-C, move to another worksheet, postion the cursor next to a blank ">" and press CTRL-V. The blue statement appears in the new worksheet, BUT...

It only appears in red (i.e. executable) if the blue statement "A:=B" covers a single line on my screen in the first worksheet.

If it covers more than one line, and I try to highlight more than one line, the pasted statement appears in blue in my second worksheet and won't execute. I've tried converting the blue statement into every format under the sun, but nothing works.  So, I've got to cut/paste line-by-line from one worksheet to another, which is not a good idea, since I might miss something. Or I've got to save expressions to files and read them, again not a good idea.

So, how do you cut/paste an output (blue) statement from one worksheet to another if the statement covers more than one line on the screen and you want it to execute (so you can carry a result into a new worksheet)? I've got my preferences set such that worksheets are independent.

I can't even find a help topic to consult. 

Thank you