Complex sentence: Louis-Hippolyte Lebas (Paris, 31 March 1782--Paris, 12 June 1867) was a French architect working in a rational and severe Neoclassical style, who was trained in the "atelier" of Percier and Fontaine, the favoured architects of Napoleon.
Split into simpler sentences: Louis-Hippolyte Lebas (Paris, 31 March 1782--Paris, 12 June 1867) was a French architect working in a rational and severe Neoclassical style. He was trained in the atelier of Percier and Fontaine, the favoured architects of Napoleon.