Some people are intimately familiar with their family history, and others don't know as much about their grandparents, great grandparents, cousins, and so on. Before you make a family tree, get all the information you need by conducting research in the following ways:  Ask family members for information. If you're making a family tree for a school project, your mother and father may be able to tell you everything you need to know about your family. For extensive family history projects, consider looking at a genealogy database. Sites like Familysearch.org have information about long lost relatives you may not have known you had. Be thorough. A family tree isn't as useful when someone is accidentally left out. You might want to check with multiple sources to make sure your information is accurate. It's interesting to trace your family history as far back as you can, but when you're drawing a family tree, it's not practical to record information that extends more than a few generations back. You're limited by the size of the paper you use, since you need to be able to fit all of the names on one page.  Many people choose to go as far back as their great great grandparents and their siblings, or their great grandparents and their siblings. These are people you, your parents or your grandparents have met, so they are tied to you more closely than more distant relatives. If you have a large family with a lot of great aunts and uncles, cousins, and so on, you may have to end with a more recent generation to fit everyone on one page. If you have a smaller family you might be able to extend the tree to a more distant generation.

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Write a summary of the previous text in Chinese:
了解你的族谱。 决定追溯到多远。