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: 'this is a group of boys with their boards'. Count the number of vowels in the given sentence.
Example Output: 12

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 black cat looking out the window at a black bird'. Count the number of consonants in the given sentence.
Example Output:
25