The phrase "looked on" can be substituted with several other similar phrases that convey a similar meaning. Some synonyms for this phrase include "observed," "watched," "witnessed," "viewed," and "seen." All of these words imply that someone is looking at something with intentionality and focus, whether it be a person, object, or event. These words can be used interchangeably to add variety to writing or speaking and can help to create a clearer picture of the action being described. It is important to choose the right synonym based on the context in which it is being used to convey the intended meaning accurately.