(American Idioms)come across
To find or meet by chance.
He came across a dollar bill in the suit he was sending to the cleaner.
Am I correct if saying that Past Continuous in the clause 'he was sending to the cleaner' implies that it was when he was sending the suit to the cleaner that he came across a dollar bill in it ? That is, if there were Past Simple instead of the Past Continuous, it would be impossible to know when it was that he came across a dollar bill. Am I reasoning correctly?