3. (A). I’m having difficulty putting the facts in order.

　　(B). I could have gotten a map at the factory very easily.

　　(C). Knowing the difficulty, I could have found a solution.

　　(D). With a map, it would have been easy to locate the factory.

　　4. (A). The door was open, but I didn’t go in.

　　(B). I opened the door myself.

　　(C). Since the door was open, I came in.

　　(D). She opened the door to let me in.

　　答案与音频文本：

　　DC

　　3. If I’d had a map, I could have found the factory with no difficulty.

　　4. The door was open, so I let myself in.