关于 and 对于: about, and to whom

The whole family on one screen

The colours stay the same all page long:

The first four open a phrase that sits in front of the real verb. The next three are verbs themselves. 终于 (zhōngyú) is an everyday adverb.

关于 (guānyú) or 对于 (duìyú)?

关于 (guānyú) says what a book, a talk or a question is ON. 对于 (duìyú) says who or what an attitude or an effect lands on:

Two places take only one of them. For what a book, a film or a talk is about, only 关于 (guānyú): 关于历史的书 (guānyú lìshǐ de shū), never 对于历史的书. With a word like 重要 (zhòngyào), important, only 对于 (duìyú) or 对 (duì): 对于我们很重要 (duìyú wǒmen hěn zhòngyào), never 关于我们很重要.

Test it in English: if "on the subject of" fits, use 关于 (guānyú); if "as it affects" or "in the eyes of" fits, use 对于 (duìyú).

对 (duì) or 对于 (duìyú)?

对 (duì) is the shorter, everyday word. Almost anywhere 对于 (duìyú) works, 对 works too; the reverse is not true. How someone treats a person takes only 对:

对 (duì) sits happily after the subject. 对于 (duìyú) is at home at the front of the sentence, as in the last row; after the subject it is more formal than 对 (duì).