fill the missing words

1. Ci_ _us clouds are high feathery clouds
2. Ni_b_s cloud is a cloud that produce precipitation
3. C_m_lu clouds are the puffy clouds that look like puffs of cotton
4. A c_ou_ is a large collection of very tiny droplets of water or ice crystals
5. S_ra_ _s clouds are uniform grayish clouds not often cover the entire sky ​