| Answer | Crossword Clue |
|---|---|
| AIRLINES | Modern transportation systems. |
| RAILWAYS | Transportation systems. |
| LINES | Transportation systems. |
| CARLINES | Transportation systems. |
| ELS | Transportation systems. |
| TRAMLINES | Transportation systems. |
| RRS | Transportation systems: Abbr. |
| ELS | Systems of transportation. |
| RRS | Transportation systems (abbr.) |
