Question

give me some tips to give a impressive saminar ,it is urgent

Answer 1

The most important thing when you are giving seminar or any kind of public speaking is CONFIDENCE, you should be really confident while u speak busy this add more weight to your content. 
second thing is to have a good precise content about your topic of discussion. 
third is be a good listener and then be a good speaker.
have good body language and straight eye contact.
try to be fluent as much as you can

hope dis helps you !!!!