If the "S" records are linked to the "L" records, I really think you should have them in a separate table with a key value linking each one back to its "L" record. That said, there's probably a way to do what you want without doing that. One question - is there anything in the "S" record that makes it obvious which "L" record it's linked to - or are you just relying on the sequence of the data in the table? Also, does every "L" have an associated "S"?
If there is a linked field then create a query which just returns the "S" records. Create a second query using the original table and link this, in the query, to the first query containing the "S". Then output data from both the table and the query in a single record from the query and you can easily display both in a single line.
If there is no common field then try this:
Change the report layout to be multi-column (two columns) and create just one set of controls for output on the left of the report.
In the detail section's Format event, you'll need to keep track of the sequence of "L" and "S" records. When you get an "L" followed by an "S" all is well. If you can get an "L" followed by another "L" then you want to skip the right-hand column. You can do this using the report's MoveLayout method. Read up about this in the Access's help.
Simon