Place your cursor at the beginning of the text you want to copy and click and hold the left mouse button. Now slide the mouse/cursor and you will see it highlighting text. When you have the text highlighted that you want to move simply let up on the button and the text will be highlighted.
Now put your cursor on the highlighted text and click the right mouse button. A list of options will show up. Click on copy and the highlighted text will be copied to an electronic "clipboard".
Now go to wherever you want to put that text, put your cursor where you want the text to begin and click your right mouse button. A list of options will show up and one will be paste. Click on the paste option and the text that you previously copied to the "clipboard" will be pasted into the spot where you had your cursor.
Hope this helps out.