Answer:
See explanation
Step-by-step explanation:
Ammonia is a covalent molecule. We should remember that a covalent molecule is formed by the sharing of electrons.
Now hydrogen has only one valence electron while nitrogen has five valence electrons. Two among these five valence electrons is a lone pair of electrons.
Three hydrogen atoms can share one electron each with all of the available valence electrons in nitrogen to form NH3 with the lone pair of electrons still localized on the nitrogen atom.