情(qíng) - feeling, emotion, affection; situation in Mandarin

情 (qíng) is feeling in the broad sense: emotion, affection, the bond between people, and by extension the state of affairs. It sits at the heart of a whole family of words, from 感情 and 爱情 to 心情, 事情 and 情况.

On its own it is mostly literary or fixed. You meet it bare in sayings and in phrases like 讲情 (to plead on someone else behalf) or 有情有义 (loyal and warm hearted). In everyday speech the compounds do the work.

The trap is treating 情 as a drop in translation of feeling. 我有一个情 is not Mandarin. If you mean an emotion say 感情, if you mean a mood say 心情, and if you mean a matter say 事情. Learn 情 as the shared root rather than as a word you use alone.