Interjections are exclamatory words ('Oh!', 'Wow!', 'Ouch!') that express emotion and often stand alone or are set off by punctuation. Exclamatory sentences end with an exclamation mark and express strong emotion. Using interjections appropriately adds voice and emotion to writing.
Look for interjections in dialogue and writing. Practice writing your own exclamatory sentences and noting how they differ from other sentence types.
You already know from your study of interjections and expletives that some words exist primarily to express a speaker's emotional state rather than to carry grammatical weight. This topic extends that understanding in two directions: how interjections behave in writing, and what makes a full sentence exclamatory.
Interjections are emotionally charged words or phrases that stand apart from the grammatical structure of the sentence around them. "Ouch!" can appear alone. "Well, I'm not sure about that." "Oh, so that's what happened." In each case, the interjection (*Ouch*, *Well*, *Oh*) is set off by punctuation — an exclamation point if the emotion is intense, a comma if the tone is milder. The same word can work at different emotional temperatures: "Oh! I didn't see you there!" (startled) versus "Oh, I see." (neutral acknowledgment). The punctuation you choose signals the emotional intensity of the moment.
Exclamatory sentences are grammatically complete sentences that express strong emotion. They end with an exclamation point, but they do *not* require an interjection. "The house is on fire!" is a fully formed declarative statement delivered with urgency — no interjection needed. "What a beautiful morning!" is exclamatory in structure but also lacks a standalone interjection word. The exclamatory sentence type is about the *intensity of feeling* expressed, not about whether a particular emotional marker word appears.
This distinction matters in writing because interjections and exclamatory sentences serve different functions even when they appear together. "Wow! That performance was extraordinary!" contains both: an interjection (*Wow*) and an exclamatory sentence. But "The whole audience stood to applaud!" is exclamatory without any interjection. Mixing them strategically controls the rhythm and emotional temperature of your prose. In formal writing, interjections are rare; exclamatory sentences appear when genuine emphasis is warranted. Overuse of exclamation points drains them of their impact — the reader stops feeling the emotion because everything is marked as urgent.