17. He decided ___________ (explain) the problem on the phone instead of sending a letter. 18. If ___________ (know) sign language, I’d be able to communicate with her. 19. They (make) …………………..their presentation at this time tomorrow morning. 20. He has decided (go)……………. to work in a school in a quite remote area. 21. Lan (sit)…………………………… on the plane at 10 am tomorrow. 22. If it doesn’t rain, what ……………. you (do) ……………......... this evening? 23. There is a link between (economy) ..................................... development and the environment. 24. Every day we hear about new (develop) ......................................... in science and technology. 25. I’ve decided (create) ……………………..a new Skype account. 26. Avoid (post) …………………… personal information on Facebook