In my survey I am asking students to explain the importance of 4 out of 5 topics using a 'multiple short text'. The 5th explanation will come from the instructor and serve as an exemplar for the students. I am wondering how the heck to do something like this

In the example below students would provide the text for <student response> and the instructor's exemplar response is provided ahead of time and is in double quotes.

Topic 1: Replication Initiation <student response>
Topic 2: Error Checking "Error checking is critical to DNA replication because errors...>
Topic 3: Lagging vs Leading <student response>
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Use the question type "text display" or include the explanation in the question text itself.

You can set input fields to readonly via JQuery. You might upload your question here to ensure the right workaround is applied.

To get an impression what I mean, here is an example to ensure that a checkbox answer is always checked.

There are other examples here in the forum.

Just a little tip to add to jelo's post - be careful when rendering inputs "disabled". If the input remains disabled when the form is submitted, its value may not be recorded in the data.

tpartner wrote: If the input remains disabled when the form is submitted, its value may not be recorded in the data.

Is that behavior depending on the browser? Or on Limesurvey and shipped JS libraries?

That is browser behaviour. All browsers should adhere to that. More info - www.w3.org/TR/html401/interact/forms.html#successful-controls .

I always do something like:

...or just use the readonly property.