问题详情：
Usually most divers don’t go very deep. Mainly they dive to a deep of about 20 meters. Then they swam around as they slowly return to the surface. Everyone wants to dive must first have diving lessons. There are the number of dangers that you have to learn about. For one thing, you might have problems with its air bottle. A diver must know however the equipment works and be able to recognize possible problem. There are also dangerous types of fish that you must look out for. You must be familiar to the environment you’ll be diving in. Before you go on a dive, make sure you know that what you are getting into. Diving may look easily, but if you don’t have the necessary training, it can be both difficult and dangerous.
【回答】
改为 改为swim yone后面加 who/that（或者Everyone改为Whoever）改为a 改为ver 改为how 7．problem改为problems 8．to改为with9．去掉that10．easily改为easy
知识点：阅读填空
题型：阅读填空
