当你在机场接留学的朋友时，可以用以下几种方式表达你的欢迎和关心：

热情问候

"Hi, you must be XXX, it's really good to see you! Especially after such a long time flight."（嗨，你一定是XXX，看到你真高兴!特别是飞行了这么长时间后。）

关心旅途

"How was your trip？"（旅途怎么样？）

"Did you find the flight comfortable？"（你觉得飞行舒服吗？）

"Are you tired？ We can go to the car and rest a bit if you want."（你累了吗？如果愿意，我们可以去车里休息一下。）

表达祝福

"I hope you had a smooth flight and that you're safe and sound."（我希望你飞行顺利，平安无事。）

"Welcome back! It's great to have you home again."（欢迎回来!再次见到你真好。）

"I'm glad you're back. Let's grab a bite to eat at our favorite restaurant. It's been a while since we last saw each other."（很高兴你回来了。我们在最喜欢的餐厅吃一顿饭怎么样？我们已经很久没见面了。）

提供帮助

"Let me help you with your luggage."（让我帮你拿行李吧。）

简单交流

"Nice to meet you again."（很高兴再次见到你。）

"Welcome to XXX. Follow me, I'll take you to the car."（欢迎来到XXX。跟我来，我带你去坐车。）

这些表达方式既真诚又热情，能够很好地传达你对朋友的关心和支持。希望这些建议对你有所帮助!