The following diagram illustrates a variant grammar that parses the following English sentence:
"The quick brown fox jumps over the lazy dog."
Valid sentences parsable by this grammar:
The fox jumps over the dog. Bold letters indicate a default value when no option is entered; therefore, entry of this statement would be interpreted as The brown fox jumps over the dog.
The quick brown fox jumps over the dog.
The red fox jumps over the lazy cat.
The quick brown fox jumps onto the tired elephant.