1. subject (For me to ask would be treason, for me to be told would be treason.)

2. predicative (That was for him to find it out.)

3. complex object (He waited for her to speak.)

4. attribute (The best thing for you to do is to tell her the truth.)

5. Adverbial modifier

a). of purpose (He stepped aside for me to pass.)

b). of result (He spoke loud enough for you to hear.)