Suppose I have 12 eggs. I drop 2 and eat 5. How many eggs do I have left?
user
Twelve eggs - two dropped eggs = ten eggs
Ten eggs - five eaten eggs = five eggs

Therefore, there are 5 eggs remaining.
assistant
What if the two I dropped landed on a pillow? And my neighbor bought me 1 extra egg and threw it at my window and broke it. the window I mean, not the egg that was fine also landed on the pillow.
user
The two you dropped survived the fall, so now 7 are left.
Then your neighbor brings you an extra egg, which survives the journey through your now broken window, so now 8 are left.
Therefore, you now have 8 eggs left.
assistant