[简答题]Read the following paragraph and underline the topic sentences.There are eight persons in my dormitory, and we are all good friends. Since we live in the same dormitory for four years , we know each other better than other students. Although we come from different places and our personality is quite different , we are familiar with each other quickly. We often do something together, such as studying, playing, shopping and watching films. When we meet difficulties, we help each other. When we have something happy, we share it together. Of course , sometimes we have also quarreling and misunderstanding, but we quickly forget it and became good friends again. I believe this kind of friendship will never be forgotten.