One of our clients will drop in our firm in 2 months, and I will meet them as a host. They will give a presentation and we may discuss some professional topics.

This will be my first experience to receive foreign guests as a master. I am extremely worrying about my spoken English.

Does anybody have good idea that can help me be able to deal with that situation at that time regardless of short time?

I will repay your help by giving teach to your Chinese or communicating with you to practise your Japanese I know some at least.