It's going to be an unforget table experience.

my unforgettable person 难忘的人

Guilin is famous with it's uniquely beautiful landscapes,it's a historic and cultural city.Elephant Trunk Hill is regarded as the symbol of Guilin landscape.Every one who mentioned about Guilin,Elephant Trunk Hill is the first world appeared in our brain.It's like an elephant drinking water from the river with its long trunk.As long as you see this hill,that means you have been to Guilin

one of my unforgetable memories of my school is that+clause

答案选B,后面是个定语从句修饰它,one是前面moment的同位语!
但是我有疑问,A选项不能引导非限定从,但可以看成的代词指代可数名词单数,表特指,相当于the one 从这个意义上理解能否选A?后面看成的定语从句.也就是说如果答案选项中有the one 的话能不能选?
再有,C答案,it可以替代前面的moment,那为什么不能选呢?同样后面可以看成一个定语从句啊,请高人指导!多谢多谢.

An unforget thing
Last Sunday I went to visit the Great Wall with my friends. We went there by bus. It took us about two hours to get there. It was hot and windy that day. There were thousands of people. When we saw a group of foreigners,we went up and talked with them. We told them lots of history of the Great Wall. They were very surprised when they saw that our English were exellent and we knew a lot about the Great Wall's history. They thanked us a lot and we really had a good time. We felt proud of ourselves and being Chinese.

一件难忘的事(An unforgetable thing)
How time flies!I'm fifteen years now.During the long time,there was one thing that I will never forget.
The Spring Festival is our traditional festival.During the Spring Festival,people usually visit their friends and relatives.When I was 9 years old,my family took the bus to my grandparents' to say "Happy New Year" to them.
In the bus,I had a good seat.At 7:30,the bus came to a village.A woman got on with a baby in her arms.At that time,there was no seat.But she must look after her baby carefully.She had to stand next to me.I wanted to stand up and let her sit down,but I was afraid of hearing the other people say"That girl want to be praised."I looked around.Most people were looking out of the windows and some were sleeping.Suddenly,a little boy behind me,stood up and made room for the woman.She said "Thank you very much" with a big smile.The boy smiled,too.When I told my cousin about it after that,he said "The child is the father of a man." I'm very ashamed.Why could't I do the same thing as the little boy did?
From that I learn that we should do our best to help people who need help.If everyone makes a contribution to helping others,the world will become much more beautiful!

你的问题有点歧义，上面的人已经将那个词语翻译了一下，但我不认为你会问这么简单的问题。要写好试卷上的书面表达，关键是审题，围绕题目要求来写，否则会扣要点分；其次，尽量不要有语法错误，能有一些句法结构比较复杂的句子；再者，要注意行文流畅，有过渡句。最后，要卷面清晰。看看，这对你有用吗？这是我多年参加阅卷工作的一些经验，供你参考。...