sentence variety
sentence variety (variedad de oraciones)
mixing short and long sentences of different types and openings so that writing reads smoothly.
Example
The plan failed. Although it had wide support, it ran out of money in its first year. (A short sentence, then a longer complex one.)
In Spanish
sentence variety (variedad de oraciones) — mezclar oraciones cortas y largas, de distintos tipos y con distintos comienzos, para que el texto se lea con fluidez.
The plan failed. Although it had wide support, it ran out of money in its first year. (Una oración corta y luego una compleja más larga.)