She looks very young. She "s about thirty years old, she has long hair, two big eyes and small mouth. She is funny, but she is strict with us."

她看起来很年轻。她大约三十岁，她有一头长发，一双大眼睛和一个小嘴巴。她很有趣，不过，她严格要求我们。

youdao

The industry's assumption has long been that shrinkage of hair-strand diameter which is just 0.075 millimeters for a person with fine-to-medium hair was too small to detect.

WSJ: Old Hair Days: Products to Help Manage Gray and Thinning Hair