If I want to be by Grand Canyon sometime this afternoon when should I leave home?
[IN:GET_ESTIMATED_DEPARTURE If I want to be by [SL:DESTINATION [IN:GET_LOCATION [SL:POINT_ON_MAP Grand Canyon ] ] ] [SL:DATE_TIME_ARRIVAL sometime this afternoon ] when should I leave [SL:SOURCE [IN:GET_LOCATION_HOME home ] ] ? ]