C501 The Promise of Childhood Sweethearts

Lau Qingmei looked worriedly at the messy small laboratory, then looked at her other sisters, who were already used to it. She whispered in Chiang Chen's ear, "Ning Hua is only in her second year of high school. Is there really no problem with doing this kind of experiment?"

"Don't worry, she knows what she's doing," he assured her, patting her on the shoulder