1. I think it is very important for students to understand and have fun during my lessons. 2. I consider my lessons depending on my students' preferences. - Apostrophe indicates ownership and if if you are making students plural then the apostrophe comes after the s. Another note: I understand what you're saying here but I think, "I format my lessons based on my students' preferences." makes your intentions more clear. 3. I use textbooks, but I prefer playing games using flashcards, anime or movies. 4. My favorite countries are Brazil and England. I want to go to Pacific islands and Africa next. - Do you mean, "My favorite countries, that I've visited, are Brazil and England. I want to go to the Pacific Islands or Africa next."? Another note: the Pacific Islands are made up of roughly 200 islands and each chain are very different (i.e. Philipines, Samoa, Hawaii, Tahiti, etc.) so maybe you'd like to specify a little more. Hope this helps:)