Grammar exercises: How to use 关于 (guānyú) and 对于 (duìyú) correctly in Chinese 语法：关于、对于、关、对、于 练习
The example sentences of the article, a few to an exercise, in the order the article shows them. Each exercise takes the point's word out of a sentence for you to fill back in, then gives you the sentence's words to put in order, and an item you miss comes back later in the same sitting.
3 grammar exercises over 26 items.