Escape character for command keywords

Is there a character we can use at the beginning of a tweet to escape command keywords like "on" (e.g., a backslash)? If I update with something like "On the roof", I end up following "the". Having to write "I'm on the roof" is definitely not ideal, especially if you have a long tweet that wouldn't fit the 140 character limit. It would be nice just to add a single character at the beginning like "\On the roof".