Why does saying yes to a tiny favor make you a little more likely to say yes to a huge one?
One easy way to raise your odds of a big yes is to ask for a tiny one first.
Once people agree to a small, easy request, they tend to become somewhat more likely to agree to a larger one later, even when the two are unrelated and there is no reward. The usual explanation is that the first yes nudges your self-image toward someone who helps or goes along, and you stay roughly consistent with it. The catch: across decades of studies the effect is modest, not the dramatic jump the famous 1966 lawn-sign experiment showed, and in many cases it does not appear at all.
You let a friend borrow 50k for lunch; a week later they ask for 2 million. The earlier small loan can make the big ask a touch harder to refuse, though it is no guarantee you will say yes.
A small yes can tilt a later big yes in your favor, but treat it as a gentle nudge, not a reliable lever.
When a request starts suspiciously small, it is worth asking whether you are being warmed up for a bigger one - while remembering the nudge is real but weak, so do not over-trust it in either direction.
Foot in the door first, the rest of the body may follow.
Learn the idea and practice English at the same time.