| 2024-12-09 | Triangular Greek letters |
| 2024-12-07 | Mouths that don't talk |
| 2024-02-18 | Some rivers have them |
| 2020-12-27 | Some U.S. space launch rockets |
| 2020-03-22 | Symbols of change, in math |
| 2016-11-29 | Areas at rivers' ends |
| 2016-04-29 | Symbols of change, in math |
| 2014-10-26 | Brackish water locales |
| 2014-07-06 | Symbols of change |
| 2010-09-17 | Some sorority women |
| 2009-11-01 | River areas named for their shape |
| 2009-10-10 | Some mouths |
| 2006-01-27 | Some fertile regions |
| 2005-08-05 | Some mouths |
| 2004-04-16 | Some mouths |
| 2003-11-07 | Fluvial plains |
| 2002-12-28 | Some fraternity members |
| 2002-03-03 | Some sorority women |
| 1999-12-24 | Flood-prone areas |