Imagine that you have ten special friends, all dressed up in their nicest clothes with lamps in their hands, waiting for someone very important to arrive at a party. This person is like a king, and they all want to be ready to welcome him when he comes.
Now, the important thing is that they don't know exactly when he is going to come. He might come in the daytime, or in the middle of the night when it is very dark outside. So they all have to be prepared and have enough oil for their lamps to last them through the whole night.
Five of your friends are very smart and brought extra oil with them, just in case. The other five didn't think ahead and only brought enough for a little while. So when it gets dark, all 10 of your friends light their lamps and wait for the important person to come.
As the hours go by, they all get tired and a little sleepy. Finally, in the middle of the night, they hear a trumpet sound and know that the important person is finally here! But when they look at their lamps, five of them have run out of oil and can't light them anymore.
The five friends who were prepared with extra oil offer to share with the ones who didn't bring enough, but they can't because there isn't enough to go around. So the five unprepared friends have to go to the store to buy more oil, which takes a very long time. By the time they come back, the important person has already arrived and it's too late to join the party.
That's the story of the Parable of the Ten Virgins. It teaches us that we should always be prepared for important things, because we never know when they might happen. Just like how your 5 smart friends were ready for the king's arrival, we should be ready for anything that might come our way.