16. Using in presentation is very important to make your speech more attractive. A. body language B. poems C. sign language D. music 17. In presentation, presenters should use their body language such as hand gesture, eye contact to communicate with the audience . A.effective B.effectively C.more effective D.more effectively 18. He don’t understand the instruction on this website, so he have to use messages. A. instant B. online C. non-verbal D. verbal 19. , dancing and painting are examples of non-verbal communication. A. chatting B. smiling C. singing D. emailing 20. Using in presentation is very important to make your speech more attractive. A. body language B. poems C. sign language D. music 21. In presentation, presenters should use their body language such as hand gesture, eye contact to communicate with the audience . A.effective B.effectively C.more effective D.more effectively