1) Not to fall in local language exacerbation's - incorrect (possessive) Not to fall in local language exacerbations correct (plural) 2) We should stop to use the washing machine - incorrect(probably) Has a different leaning. = On leaving the bathroom, we should all stop to use the machine. = On leaving the bathroom, we should all stop and use the machine. We should stop using the washing machine - correct. Use the machine 3) They just air their jeans from time to time and remove any stains - correct They just air their jeans from time to time and remove some stains on - "on" incorrect, and "some" strange. 4) We throw less toxic water in the sewer correct - in We throw less toxic water by the sewer - correct, but unlikely, it means beside, alongside, adjacent to FULL STOPS? Periods, if you like. Sentences end in a full stop, or question mark, or similar.

Not to fall in local language exacerbations We should stop using the washing machine They just air their jeans from time to time and remove any stains We throw less toxic water in the sewer