—Paul, can I borrow this book from you?
—Yes, of course. But I ________reading it. What about this Saturday?
A.don't finish B.wouldn't finish
C.hadn't finished D.haven't finished
答案：
D
【解析】
句意：——保罗，我能向你借这本书吗？——是的，当然。但我还没读完。这个星期六怎么样？
考查考查时态。根据语境结合设空处Yes, of course. But I ________reading it.可知，强调对现在的影响，所以用现在完成时。现在完成时的构成是：主语+have/has+动词的过去分词；变否定句在have/has后面直接加not ，应填haven't finished ，故选D。