| # | Concept | Culture | Statement | Freq. |
|---|---|---|---|---|
| 1 | key date | US | Refers to significant historical events, such as the signing of a declaration or the start of a war. | 1 |
| 2 | key date | United States | A key date can refer to an important historical event, such as the signing of a declaration or the start of a war. | 1 |
| 3 | key date | United States | A key date is an important deadline or event in a project or schedule that must be met. | 1 |