In this task, you need to count the number of vowels (letters 'a', 'e', 'i', 'o', 'u') / consonants (all letters other than vowels) in the given sentence.

Example Input: Sentence: 'a crew of people looking at an airplane'. Count the number of vowels in the given sentence.
Example Output: 15

Example Input: Sentence: 'father and son wait on their bicycle at a traffic light'. Count the number of vowels in the given sentence.
Example Output: 16

Example Input: Sentence: 'a modern kitchen has an abundance of counter space'. Count the number of vowels in the given sentence.
Example Output:
17