Common Mistakes : Before

Adverb

.BAD: Before forty years the journey took twice as long

.GOOD: Forty years ago the journey took twice as long

.BAD: Not so long before we used animals for transportation

.GOOD: Not so long ago we used animals for transportation

ago = before ‘now’, the moment of speaking

.Her plane landed ten minutes ago. In fact, here she comes now

(I saw him just five minutes ago. (=five minutes before now

before = before ‘then’, a time in the past

I went to the airport last Monday to meet Sue. I hadn’t been to the airport
(before. (= before last Monday

(I saw him last Friday in London and two days before in Leeds. (= last Wednesday

.BAD: My parents first came here before 40 years ago

.GOOD: My parents first came here 40 years ago