0 If a person or business selling goods throws something in, they provide it for free when you buy something else from them: --
When I bought my new glasses, they threw in a free pair of prescription sunglasses.
1 to give customers a free product or service when they buy something: --
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.