You want to welcome this new classmate to your class. Then you should say welcome. We can study together. We are all very happy because we have a new classmate. I hope we can help each other in our studies. Encourage each other. Everyone likes you very much. I hope we can become best friends and classmates. And I think this kind of friendship between classmates is the deepest and purest. Maybe after many years, the students' feelings are still quite pure. I hope this kind of classmate love can last for a long time, help each other in their studies and get recognition from each other.