0 past simple and past participle of double --
1 to become twice as much or as many, or to make something twice as much or many: --
The government aims to double the number of students in higher education within 25 years.
Company profits have doubled since the introduction of new technology.
We can complete it step by step however long the road is and it can't be completed however short the road is if you don't even mark your footprint.
Можем да го завършим стъпка по стъпка, колкото и дълъг да е пътят и не може да бъде завършен, колкото и кратък да е пътят, ако дори не маркирате отпечатъка си.