Is it appropriate to underline key words in an exam answer? Some exams I have to take involve redacting long answers about a given subject. I know the corrector has to correct hundreds of exams, so clarity in both expression and calligraphy is key to set the corrector in the right mood in order to get a higher grade. I usually tend to be too circumlocutory, but in certain contexts explaining a term requires long descriptions that could make the key word "vanish" among a lot of explanatory sentences. A solution to that is to repeat the key word every couple of sentences, but that would only result in a waste of time (which is of paramount importance, since time is usually the limiting factor for me), and a verbose prose that is precisely what I'm trying to avoid.

In order to highlight such words, I usually italize them when writing a paper, but that looks plain wrong in hand-written texts, where italic letters are not so evident. So I underline them instead. I feel that should make the corrector task easier and faster, since that way they only have to scan the text looking for the key words to make sure the student has commented everything they were supposed to. I even had a teacher who highlighted such words herself prior to give a final grade.

However, I'm not sure how "standard" it is to underline key words, or whether it is regarded as a sign of poor writing style rather than an appreciated aid for correctors. I recently read from a well-known Spanish author that italic words were disrespectful to the reader since they were somehow telling them which words they should focus on, as if they were unable to work that out on their own. People in this post seem to agree it is not a good idea, but their alternative is to write a short abstract to sum up all the ideas they would italize otherwise. However, as you can tell, that's not an option when writing an exam answer.

So, should I underline key words when writing long exam answers?

Is there even a consensus about it, or does it simply depend on the corrector preferences?



Note: The scope of higlighting key words is not to make the correctors notice I've mentioned them, but just to make the correcting task easier.

Note: I'm not a native English speaker and I don't take exams in English, so please don't take this question as a sample of my writing skills. I can do better.
I do not believe that there is a strong consensus on use of textual emphasis in scientific writing.  In publications, I have often seen people use italics (and done so myself) to designate the first use a word in its definition; I have rarely (but occasionally) seen them used for emphasizing a key phrase.  Typically, in scientific writing one is expected to make the key phrases clear through prose alone---but of course, there are tricks to improve the visibility of key phrases in prose, such as use of lists, position of a phrase within a paragraph, etc.

In an exam, since things are handwritten and there is little chance to revise, I would expect standards to generally be more flexible.  Certainly I personally might find it a bit odd, but not at all problematic, for a student to underline words or phrases.  Your professors may or may not agree with me---as I said, I do not think there is any strong consensus.