Grants or takes technology means the tech points go up or down. Usually only by a few so it is rarely noticeable.
Grants or takes wisdom increases or decreases a villager's skills. Sometimes it is the one banging the gong, sometimes it's a random villager.
Grants luck means an island event will happen in the next few minutes.
Grants or takes food either changes the amount of food in the food bin, or adds or takes away coconuts and/or crops.