A year ago (give or take a month) I looked into the difference between 'replace', 'substitute' and 'exchange', saying that we replace the 'old' with the 'new', we exchange the 'old' for the 'new', but we substitute the 'new' for the 'old'. Another way of trying to remember could be to associate these words with specific contexts, like exchanging one currency for another, Slovak crowns for euros for example, at an exchange office.

You replace damaged or worn out bits of your car with new parts, which are called replacement parts. The football (soccer) coach (say /kouč/) substitutes a fresh player for a tired or injured one, and either side can make three such substitutions during the game from the substitutes' bench. In cooking, some people try to substitute "tehla" for parmesan on the spaghetti - in that case it expresses something of the idea of "podstrčiť", which is not present in replace or exchange.