493、( )3.Traveling is a very good activity.When you are fed up with your work and are allowed to take a holiday， you can go to the beautiful spots to enjoy the beauty of nature and the special character of other cities.You can breathe fresh air， visit some places of interest， meet different people and make friends with them.Then you will feel fully relaxed and you will have the energy to undertake the new tasks waiting for you.But sometimes， traveling is not an enjoyable thing.For example， when the bus or car you take has a bad accident， you may be trapped in it and waste your timE. What＇s more， the weather can be changeablE. If you are climbing a mountain， it may rain suddenly.You may be caught in the rain and may catch a colD. The worst thing is that you may have your money stolen and you may have an injury.All these are temible things that can happen to a tourist.Therefore， before going on a trip， you must prepare yourself carefully.Firstly， you must have clear information about the weather.Secondly， you should choose a good companion so that you can help each other.Thirdly， you must be careful everywhere and try to avoid accidents.If you do these， you can enjoy your travels better and reduce unnecessary troublE. What is not mentioned in the passage () ?