留学生在交流时，可以使用以下几种表达方式：

问候和自我介绍

打招呼：Hi/Hello/Hey, how are you？/How's it going？/What's up？

回答：I'm good/fine/OK, thanks. And you？/Not much./Just chilling./Same old, same old.

自我介绍：My name is.../I'm...

描述来源：I'm from.../I come from...

表达祝福和鼓励

祝福：May your studies be fruitful and your life filled with joy and success.

鼓励：Believe in yourself and never give up, even in the face of challenges.

表达怀念和关心

怀念：I miss you all the time.

关心：Don't forget to keep in touch with your family and friends.

日常生活用语

询问：What's up？/Sup？

表达紧急：ASAP （As soon as possible）

表达原因：BC/cuz （because 的缩写）

顺便一提：BTW （By the way）

表达知识分子特质

骨气：We should stand firm and not compromise our principles.

爱国：We should contribute to our country and society with our knowledge and skills.

表达期待和承诺

期待：I'm looking forward to this new adventure and the opportunities it will bring.

承诺：I promise to give my best in my studies and return to serve my country.

以上表达方式可以帮助留学生在海外更好地融入当地文化，同时也能够表达他们的情感和想法。