Question

polar water molecules form hydrogen bonds with each other. in liquid water, hydrogen bonds are constantly broken and reformed as water molecules slide past each other.
the model shows the water molecules interacting with each other.
complete the sentence.
a slightly oxygen atom in a water molecule forms a bond with a slightly hydrogen atom in another water mol

Explanation:

In water molecules, oxygen is more electronegative than hydrogen. This causes the oxygen atom to have a slightly negative ($\delta^-$) charge and the hydrogen atoms to have a slightly positive ($\delta^+$) charge. Hydrogen bonds form between the slightly negative oxygen atom of one water molecule and the slightly positive hydrogen atom of another water molecule. Covalent bonds are within a single water molecule (between O and H), while the bond described here between different water molecules is a hydrogen bond.

Answer:

A slightly $\boldsymbol{\delta^-}$ (negative) oxygen atom in a water molecule forms a $\boldsymbol{\text{hydrogen}}$ bond with a slightly $\boldsymbol{\delta^+}$ (positive) hydrogen atom in another water mol.