修改的地方如下：
Hello，everyone! I am very happy that I can sand here to have a specch
（speech注：很多人开场白会这么讲：I am very glad to have the oppotunity/chance to launch a speech here.).
This is the first time that I have a English speech.
(这句把a改成an就没有语法错误了。个人觉得像课堂上这样的演讲，应该尽量避免用从句，用一些简单句就可以了。毕业论文里的英语要正式些。这里可以说：This is my first speech. )
If my speech isn't good, please forgive me.
（这句话是中国式的客气，美国人一般不会这么讲。forgive这个单词是一个很严重，正是的词，表示在犯了不可饶恕的错误时请求别人原谅时用。这里用excuse就可以了。美国人一般会比较直接一些，根据自己当时的情况说自己有点紧张之类的话，请观众给他鼓励。承接上面的那句，可以说：well, I am a little bit nervous, and hope you can back me up.,如果说完后，同学们有鼓掌，那你就顺势说一声Thank you./thank you for your support.)
Today, my topic is my hometown--Jiaxing. Jiaxing is our hometown, we should know more knowledge about it.
(这两句之前的称呼不对应。My和our这两个有冲突。你现在上高中，班上人应该都是嘉兴人吧。所以第一句里面的my hometown要改为our hometown.第二个句子要有关系词，两个主谓结构的句子之间一定要有关系词，不能并列。可改为since Jiaxing is our hometown, we should know more about it. Knowledge 这里可以省略。Knowledge 是一个比较正式抽象的词，更偏向于学识，学问。例如He is poor in money, but rich in knowledge. 他贫于金钱, 但富于学问。这句里money和knowledge俗雅就形成了对比。另外，句子里的it 可以用her来表达，表示更人性化，就好像我们把祖国比喻成母亲。）
First, let us see some introduction of Jiaxing.
（建议改为By this speech, I want to give you a brief introduction about Jiaxing. ）
This is the city tree of Jiaxing. And this is the city flower. Jiaxing has many specialty
(specialties要用复数形式跟many对应。), let's see.(这里可以用：for example,例如)
These are Jiaxing Wufangzhai zongzi.
（这句的复数形式不对，其实这句话可以省略，说完for example 之后，直接点开图片，说嘉兴粽子就可以了。）
Jiaxing also has lots of famous people.(A lot of famous people were born in Jiaxing. Let's see.（Let’s see这个词上面已经用过了，要避免重复，可以这样说：Let’s scan some photos.） This is Yu Hua. This is Xu Zhimo. This is Jin Yong. This is Feng Zikai. Jiaxing is a beautiful city, let's have a good look about the beauty of Jiaxing. This is Santa. This is the south lake. Where is this? This is Xiuzhou district of the new government.
（This is Xiuzhou New Official District. 应该是XIUZHOU政务新区吧？我是按这个翻译的。)
I'm very proud of my hometown is Jiaxing.
（把is 去掉，或把of换成that。根据下面的句子，这里用that比较好。）
And I am proud of that I am a people in Jiaxing.
（这个句子跟上一个句子结构应该相同，但是语义要更进一步，可以这么说：I am also very proud that I was born in Jiaxing. People这里不对，注意单复数之间的对应。）
I love you, Jiaxing. I hope after my speech, you will love Jiaxing more. My speech is over, thank you!
注：在句中有First这个词表示首先，而在接下来的介绍中没有相对应的表示顺序的词。所以文中的FIRST完全可以省略。你的内容主要分为四部分：市树市花，知名小吃，名人，知名景点。知名小吃只举例了一个，可以再加2~3个。这四个部分前面可以加first，second，third，fourth这样表示顺序的词，表示一种并列。但是这种说法一般都比较单调，更多的用： First of all, to begin with, 表第一点，secondly, then，表第二点，thirdly, what’s more, 表第三点，fourthly, at last, finally 表示第四点。
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