Why put a bar of soap in the cupboard to stop bugs?

Mix the broken soap or washing powder with water, put it in a shallow dish and put it on the balcony window sill or yard. Because the smell of soap and washing powder will make mosquitoes mistakenly think that there is food in the dish, they will fly to lay eggs in the dish, and mosquitoes should not grow in alkaline water, so you will find that mosquitoes will drown in the dish after 3-5 days.