| A | B |
|---|
| we got married | in 1989 |
| we've been married | since 1989 |
| Dinosaurs | lived in many parts of the worls |
| Many of today's diplomats | have lived in many parts of the world |
| The invention of computers | has had a dramatic effect on the modern world. |
| The arrival of Don Cortes | had a dramatic effect on the old Aztec world |
| This is the first time | we've met. |
| That was the first time | we met. |
| I haven't been to Brighton | since Tuesday. |
| I didn't go to Dublin | yesterday. |
