In addition to my previous questions, I have the following question in your edited version as follows.<br /><br />you edited the sentence as follows. But don't you think you omitted "to" for example, ...sanitaiton system to separate urine and feces from the source....<br /><br />What I meant to express here is that the sanitaiton system is designed to separate urine and feces...<br />please clarify your edition and let me know soon as I need to submit it soon.<br /><br /><br />