Final answer:
A molecule with two atoms and no lone pairs has a linear shape, a molecule with four atoms and no lone pairs has a tetrahedral shape, and a molecule with two atoms and two lone pairs has a bent shape.
Step-by-step explanation:
A molecule with two atoms and no lone pairs around the central atom has a Linear shape.
A molecule with four atoms and no lone pairs around the central atom has a Tetrahedral shape.
A molecule that has two atoms and two lone pairs around the central atom has a Bent shape.