Hey how i can increase delay in typewriter effect when last character of full text is dots?

public AudioSource audioSource;

    public float delay = 0.1f;

    public string fullText;
    public string currentText = " ";

    IEnumerator DialogueWrite()
    {
        for (int i = 0; i < fullText.Length; i++)
        {
            currentText = fullText.Substring(0,i);
            this.GetComponent<Text>().text = currentText;
            audioSource.Play();
            yield return new WaitForSeconds(delay);
        }
    }

    public void StartDialogueWriter()
    {
        StartCoroutine(DialogueWrite());
    }

Hey, how i can increase delay if it comes to the end of the sentence or a comma?

Like undertale’s intro scene

[SerializeField] private AudioSource audioSource;
[SerializeField] private Text text;
[SerializeField] float delayBetweenCharacters = 0.1f;
[SerializeField] float delayAfterPunctuation = 0.1f;
[SerializeField] public string fullText;

IEnumerator DialogueWrite()
{
    WaitForSeconds waitBetweenCharacters = new WaitForSeconds(delayBetweenCharacters);
    WaitForSeconds waitAfterPunctuation  = new WaitForSeconds(delayAfterPunctuation);
    for (int i = 0; i < fullText.Length; i++)
    {
        text.text = fullText.Substring(0,i);
        audioSource.Play();
        yield return fullText _== '.' || fullText *== ','*_

? waitAfterPunctuation
: waitBetweenCharacters;
}
}

public void StartDialogueWriter()
{
StartCoroutine(DialogueWrite());
}