Nowadays, children's early education has been popularized in this competitive society. Every parent wants their future generation to learn more and know more, and mathematics ability is always a key aspect. Previous study has shown 3.5 years old is the earliest age for children to show calculating and counting ability. However, before developing counting ability, we believe children always know numbers but they just can not say it out loud. This study's purpose is to find out when the children can describe things by numbers correctly. This study will use pictures of different numbers of items and ask the question of "how many". We expect children from 2 to 3 can show some understanding of numbers from 1 to 10 but may have troubles afterwards. Children older than that will fit the results of previous study. This study can contribute to future studies in early education and development and help researchers to know the young children's math ability.