если бы ты принял его предложение,

если бы ты принял его предложение, ты бы давно работал в хорошей фирме

Результаты (английский) 1:

If you had accepted his offer, you would have long worked in good company

Результаты (английский) 2:

if you accepted his offer, you would have long worked in good company

Результаты (английский) 3:

If you took his proposal, you would have long worked in a good firm