As someone said on another thread recently, you can write your due dates into your actions. For example, instead of just writing the action "write page 3 of report", you can write "write page 3 of report by Fri Feb 22" or "write page 3 of report by Fri Feb 22 for finishing report by Wed Feb 27". Then when you review your actions, you'll know which ones are more urgent.
I think the GTD way generally is not to worry so much about deadlines, but to go ahead and get things done far enough ahead of the deadline that you don't have to worry. Weekly review is supposed to remind you of the deadlines and help you get a feel for which things are more urgent (or important). As I see it, GTD weekly review is supposed to get things into your head, as opposed to capture which is supposed to get them out of your head.
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