What is the character of being firm outside and soft inside? Soft outside and hard inside?

Hard on the outside and soft on the inside: it's not just a knife mouth and a tofu heart. Mainly refers to the appearance looks very strong, everything wants to be top-notch, but the heart is very hot, kind and even fragile. In order to cover up the inner fragility, the appearance looks strong.

Soft on the outside and hard on the inside: it looks weak on the surface. It's a pity if you don't shake the wind, but inside, you are strong. You have your own ideas, don't follow the trend, have the determination and courage to shoulder the heavy responsibility with your seemingly weak arms.