答案：【解析】：本题主要考查阅读理解的能力，需要从给定的英文故事中提取关键信息来回答相关问题。题目类型属于阅读理解题，主要针对八年级学生的英语水平进行考查。
1. 对于第一个问题“What was the turtle's main problem?”，需要从故事中找出乌龟遇到的主要问题。根据故事中的描述，“Just last month, I swam straight into a plastic straw. It got stuck in my nose! Since I can't reach my own nose, I couldn't get the straw out.”，可以确定乌龟的主要问题是鼻子被塑料吸管卡住了。
2. 对于第二个问题“Where did the turtle meet the two humans?”，需要从故事中找出乌龟与两个人相遇的地点。根据故事中的描述，“After some time, I was tired, and I swam to the beach to have a rest. Two humans came over.”，可以确定乌龟是在海滩上遇到这两个人的。
3. 对于第三个问题“How did the turtle feel when he first saw the humans?”，需要从故事中找出乌龟第一次看到这两个人时的感受。根据故事中的描述，“As they came close, I was scared.”，可以确定乌龟第一次看到这两个人时感到害怕。
4. 对于第四个问题“How did the humans help the turtle?”，需要从故事中找出这两个人是如何帮助乌龟的。根据故事中的描述，“One of them held me, and the other carefully pulled the straw out of my nose.”，可以确定这两个人通过一个人托住乌龟，另一个人小心地将吸管从乌龟的鼻子中拉出来来帮助乌龟。
5. 对于第五个问题“What did the humans do after helping the turtle?”，需要从故事中找出这两个人在帮助乌龟之后做了什么。根据故事中的描述，“They put me back into the water. I turned back once and saw them picking up plastic from the waves.”，可以确定这两个人在帮助乌龟之后，将乌龟放回水中，并捡起海浪中的塑料。
【答案】：
1. The turtle's main problem was that a plastic straw got stuck in its nose.
2. The turtle met the two humans on the beach.
3. The turtle felt scared when he first saw the humans.
4. The humans helped the turtle by holding it and carefully pulling the straw out of its nose.
5. After helping the turtle, the humans put it back into the water and picked up plastic from the waves.