Learn Chinese Grammar: 关心(guānxīn=to care about) vs. 在乎(zàihu=to care about)

关心(guānxīn) is used to care about people or issues with emotion. Usually, you want to do something to help him/her/them or solving the problems.

在乎(zàihu) is used for people (frequently) or thing you feel very important and always think about her/him/it/them.

Example:

She does not only care about you, but also always cares about you in her mind all times.

她(tā=she)不但(bùdàn=not only)关心(guānxīn=to care about, to want to do something to help)你(nǐ=you)，而且还(érqiě hái=but also)在乎(zàihu=to care about in mind all times)你(nǐ=you)。