Cumulative sentence

A cumulative sentence begins with a short main clause and then adds a series of free modifiers that go back over it in closer and closer detail, so the sentence deepens rather than advances.

He waited in the doorway, coat over one arm, watching the hall fill and empty and fill again, counting the faces he did not recognise, certain by now that she was not coming.

The first five words are the whole grammatical sentence. Everything after them is a free modifier added at the end: an absolute phrase, then three participial phrases, each one going back over the same moment at closer range.

That is the distinguishing feature. A compound sentence moves forward — this happened, then this happened. A cumulative sentence stays put and gets sharper, which is why it reproduces the rhythm of attention so well: you see the man, then the coat, then what his eyes are doing, then what he has concluded. The last layer is usually the one carrying the meaning.

Two shapes are worth naming. In the coordinate version, the additions all sit at the same level of detail, each returning to the base clause, as in the example above. In the subordinate version, each addition modifies the one before it, so the sentence narrows steadily: watching the hall, watching one man in particular, watching the hand he kept in his pocket.

It is also the most useful sentence shape for interiority, because the final clause can be a judgement the character has just arrived at, and the layers before it are the evidence they arrived on.