H2O−104.5∘(sp3 with 2 lone pair at O ) NH3−107∘(sp3 with 1 lone pair at N ) CH4−109.5∘(sp3) H2S−92∘(sp3 with 2 lone pair at O ) Lone pair-bond pair repulsion in H2S will increase because 'S' has lower electronegativity than 'O'. So there will be lesser electron density on 'S' and thus H−S−H bond angle will be smaller than H2O.