Extracting the first few words from a string.

I have a need to extract the first 50 words from a string using Nintex Workflow (2013 On Prem).

Using a regular expression and extract, it works to a point as long as there is no punctuation. However, it's a news paragraph I'm trying to limit to a certain number of words, so punctuation is a must . I then want to create some HTML code to include a Read More Link after the truncated text.