阅读理解。 One day, when we had been riding in the burning sun for five hours, we came to a narrow, shaky bridge where a railway crossed a stagnant (发臭的) pond. For 30 feet there was nothing but the widely-spaced wooden sleepers under our wheels, and nothing to stop us from falling into the steaming bot below if we overbalanced. Right under the bridge lay the body of a dead cow. I watched Mat as hc approached the bridge and rode straight over, without even slowing down. I stopped. 'What's up?' he shouted, from the other side. 'I'm not riding over that thing. If I fail, I'll be there with that cow!' 'There's nothing to it. I just did it, didn't I?' 'You're stronger and taller. My feet can't touch the ground. You do it for me!' Mat said strength didn't come into it and rode off,leaving me staring down into the sickly brown soup . He would be waiting for me around the next corner, but I knew he would oive me at least ar hour before coming to help. The sun burned my face; sweat ran off my forehead into my eyes and stuck my shirt to my body; mosquitoes flew into my mouth when I breathed. To stand still in this place was to kill myself; anyway, to sit around waiting for Mat to help was more than my feminist pride could take. I rode back along the track a f'ew hundred yards to get a good run-up (助跑) and over I went. Mat was right: all the obstacles were in my mind. 1. The author stopped near the bridge because _____. [     ] A. she was tired and wanted to have a rest B. she found a dead cow under the bridge C. she was afraid of failing off the bridge D. she didn't know how to cross the bridge 2. Why did Mat refuse to help the author? [     ] A. He wanted to finish the journey as soon as possible. B. He felt she should overcome her fear by herself. C. He didn't believe she was really afraid. D. He knew she was too proud to accept his help. 3. What does the underlined part 'sickly brown soup' in the last paragraph ref'er to? [     ] A. The body of a dead cow. B. The mud on the wheels. C. The dirty water in the pond. D. The author's food for the journey. 4. According to the last paragraph,the author seems to believe that _____. [     ] A. nothing is difficult to the man who will try B. a friend in need is a friend indeed C. you can't make something out of nothing D. well begun is half done