H2O is a liquid whereas H2S, H2Se and H2Te are all gases at ordinary temperature. This is because, in case of water, hydrogen bonding causes association of H2O molecules resulting in higher boiling point of water than the other compounds. On the other hand, there is no such hydrogen bonding in H2S, H2Se and H2Te.
Similar is the case with HF and HCl. Both contain hydrogen attached to an electronegative element. However, in HF, hydrogen atom is attached to the more electronegative fluorine atom. So the extent of hydrogen bonding is more in case of HF, so it is a liquid and HCl is a gas.