For my money, log on to a system or log in to a system are interchangeable, and depend on the metaphor you are using (see comment on your ... ... <看更多>

Log into Facebook to start sharing and connecting with your friends, family, and people you know. ... <看更多>

Red arrow pointing to the red Continue button to login, then the enter your password. Open the Pinterest app; Enter your email address and hit Continue, ... ... <看更多>