These are tricky even for people who know English. For number one David and I is the proper way to say it Number two is once again the proper way to say it but people don’t always say it like that Number three is each other and is probably the hardest of all of these because they pretty much mean the same thing as one another Number four is I even though most people would say it is me the proper way to say it is it is I Number five would be oneself most would think it’s themselves but the proper way to say it is one self
