Indican oposición o contraste entre oraciones: but, yet, however, in contrast, on the other hand.
Ejemplo.
Copernicus views on the universe were exposed in a treatise entitled De revolutionibus orbitum celestium, completed by 1530; but published only in 1543.
We live on this planet thanks to plants. Plants protect soils from erosion, regulate the atmosphere, and prevent the formation of deserts. Yet, we are
destroying this life-support system at an alarming rate.
Curso de Comprensión de Lectura en Inglés
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