Covalent bonds are formed when two atoms share electrons. The pairs of electrons which are shared between atoms and hence number of covalent bonds, can be represented by the number of lines drawn between the symbols for the atoms. For example, a single bond is represented by a single line drawn between the atomic symbols to give the structural forumla. Complete the structural formulae for the molecules below by dragging the appropriate bonds into the boxes between the three atoms.

Question

O O N N F F

Answer 1

Apparently there are two or more structures you are to draw since the question talks about three atoms.
Are the two groups of atoms
O O N and
N F F or some other arrangement?