Just like any other clip, you can move text clips around on the time line. To make the text clip longer, simply click on the left or right side and drag to lengthen.
Resizing a text clip
To change the text, its position, color, drop shadow, background and many other properties, double click a text object or right click on a text object and choose "Edit Text..." This will bring up the text editor.
•Editing scrolling text