Choose the word or phrase that is not correct in standard English
1. I always keep the window open so as to letting the fresh air in
2. Lan tidied the bedrooms and cleaned the windows since yesterday
3. He is going to get to work earlier in order impress the boss
4. Da Lat is known like a city of pines, waterfalls and flowers
1. letting --> let
2. tidied --> has tidied
3. order --> order to
4. like --> as
1 letting => let
2 tidied => has tidied
3 order => order to
4 like => as