请认真阅读短文,并根据短文内容回答问题。
I went back to the woods and made a tent with some blankets. I put all my things inside and then I took my fishing line and went to catch a fish for dinner. During the next three days, I explored the island. I found strawberries and grapes. There were raspberries (山莓) and blackberries too, but they were green and not ready to eat.
On the fourth day I found a campfire. It was still smoking. “Somebody else was living on the island! Who was it?” I felt scared so I took my gun and climbed a tree. I watched for a long time but I didn't see anyone. I went back to my tent and tried to sleep. I didn't feel safe any more. The next day I went exploring. I kept my gun with me all the time. After a while I saw a fire through the trees. I went up to it very slowly and very quietly. A man was lying on the ground near the fire. He was asleep but there was a blanket over his head so I couldn't see his face. I hid behind a bush and waited...
—Adapted from Robinson Crusoe
回答下面5个问题,1~4小题每题答案不超过5个词。
1. How many days has Robinson been on the island at least according to the passage?
2. Why didn't Robinson eat the raspberries or blackberries he found on the island?
3. What did Robinson do on the island? (List one thing.)
4. How did Robinson feel when he found the campfire was still smoking?
5. Why did Robinson climb a tree after seeing the campfire?
