情 qíng is a pictophonetic compound: 忄 (the heart radical) carries the meaning, and 青 qīng supplies the sound. The left element 忄 is the squeezed, side-standing form of 心 xīn (heart), the same radical that marks 怕 pà (fear), 忙 máng (busy), and a whole field of inner states. On the right, 青 qīng (the blue-green of growing things) lends its pronunciation and nudges qīng toward qíng. Together they name what stirs inside: the movements of the heart.

From that core image the character spreads into three senses that anchor a great many words:

1. Feeling, emotion, mood. The general inner state: 感情 gǎnqíng (feelings; affection), 心情 xīnqíng (mood), 情绪 qíngxù (emotions; emotional state), 热情 rèqíng (warmth; enthusiasm).
2. Affection, love. Feeling directed at another person: 爱情 àiqíng (romantic love), 友情 yǒuqíng (friendship), 亲情 qīnqíng (family affection), 情人 qíngrén (lover; sweetheart).
3. Situation, circumstance. The shape of how things stand: 情况 qíngkuàng (situation), 情形 qíngxíng (state of affairs), 事情 shìqíng (matter; affair), 情节 qíngjié (plot; circumstances of a case).

The thread running through all three is the heart facing the world. Turned inward it is mood and feeling; turned toward a person it is affection; turned toward events it is the felt shape of a situation. Chinese keeps these close together on purpose: a 情况 is not a cold set of facts but the way matters actually stand, the circumstances as the heart reads them.

When 情 turns toward another person it becomes the language of bonds. Chinese sorts these bonds by who they are with. 爱情 àiqíng is romantic love, the love between partners. 友情 yǒuqíng is the feeling between friends, friendship. 亲情 qīnqíng is the tie of blood, the affection within a family. Each pairs 情 with a different first character, and together they map the heart's attachments.

This is why 情 alone can stand for romance: 情人 qíngrén is a lover or sweetheart, 情书 qíngshū is a love letter, and 情人节 Qíngrénjié is the name for Valentine's Day. The single glyph carries enough of the heart that, in the right company, it reads as love itself.

The third great sense of 情 steps away from private feeling toward the wider shape of events. Here 情 means the situation, the circumstances, the way things stand. 情况 qíngkuàng is the everyday word for "situation" or "circumstances": 什么情况 "what is going on," 情况紧急 "the situation is urgent." Its close neighbor 情形 qíngxíng describes the state of affairs as a scene one observes.

This is also where 情 meets the very common word 事情 shìqíng, a matter or affair, where 事 shì (matter) and 情 sit side by side: 有件事情 "there is a matter (to discuss)." The link is worth holding onto: in Chinese a "matter" is not a bare event but a thing with a felt shape, which is exactly what 情 contributes.

Put your finger on the heart radical 忄 at the left of 情 and feel it as a heart standing on its side, leaning toward the world. The phonetic 青 qīng, the fresh blue-green of growing things, gives the sound and a hint of something alive and stirring. 情 is the heart in motion.

Then watch which way the heart turns. Turned inward, it is mood and feeling (心情, 情绪, 感情). Turned toward a person, it is affection and love (爱情, 友情, 亲情). Turned toward events, it is the felt shape of a situation (情况, 事情). Whenever you meet 情, ask where the heart is pointing, and the sense will follow.