How to convince a client to use responsive typography

I am having trouble trying to explain to my client in a non techie language, on why he should follow responsive typography.

Let me give a little bit of context: The project in question is for creating a web portal with dynamic quiz based content (we ask users questions and then reveal the answers to them). So, in the backend I have setup a rich text editor for the client using which he can fill up the question box and the answer box. The rich text editor is needed because our questions need symbols/images attached inline and have ways to highlight part of the line in a different color.

Now, my client is obsessed with "fixing" which part of the sentence will be in which line. For example, lets say we have a question:

"Jack is looking at Anne, but Anne is looking at George. Jack is married, but George is not. Is a married person looking at an unmarried person?"

My client would insist that, for example, the first line should ALWAYS start with "Jack" AND end with "Anne", second line should be from "is looking... George",third line should be "Jack...George" and finally fourth line "Is a married...person", and so would give a forced line break after "Anne", to make it go to the next line, and same with the other lines. He would check the result in his computer to ensure everything looks good, and be happy that the text would look this way everywhere.

The trouble is that the question/answer box is meant to be responsive and adjust according to window width, and forced line breaks would cause the text layout to go haywire.

I have tried explaining this to him on several occasions, but every time I do, he seems to get irritated and says "it does not look good", "There must be a way you don't know of", and would show me how its easily done in say power point, and I would strain to explain that power point isn't the same as web.

How should I go about trying to explain that what he's doing isn't manageable/maintainable? Maybe point him to a very basic article with some do's and don'ts of responsive typography ? I googled for some but all of them assume that the reader is a designer himself.