Until now, too many people think an ant is a good insect. Even we express the ant as a symbol of dilligence in “Ant and Grasshopper”. But the ant might be troublemaker in our house or some building. There are some reasons. First of all, the ant can live house or building as well as soil. It’s start of problem. Then they spread so quickly. Once the ant comes into building, we can find the insect anywhere inside. How do they built their home? Here is the answer, and it is the second problem. Thet is they make hole on the wall for their way or home. They can pierce wood, concrete, even plastic. Lastly, worst point is that they can bite us. Especially, if a red ant bite us, it will be pretty painful. We’ve believed the ant is a good insect, but we’ve caught in a trap.