Many English teachers here will tell you that there is a lot of grammar correction needed with students. I am currently raging a one man war on the word 'Finished'. It's easy to pronounce, spell and understand. Unless, seemingly, you are a Korean student. If you are you will only be able to say "FINISHEE". It takes a lot to make me angry in the classroom or to make me feel deflated but my Kryptonite has been found.
Despite constant efforts my 'War effort' is looking totally pointless and utterly futile. I take a metaphorical bullet in the back every time I hear the word in class which hurts when you have thirteen students shout it when they finish their test at separate times. Scientific analysis by me reveals that these students are incapable in accepting that the /ed/ ending has a /t/ sound and refuse to accept correction. I wonder if it is contagious.