Neutralization of masculine in english

Student can take his or her class only when he or she wants
- someone
If someone is in distress people are always available to help him/her whatever may be the time of the day.
- one
So, the point is that there are situations in life, when one has to do something
he/she doesn't like.
However, one of the textbooks for medical college students shows the appearance of sexist language. That is, the word person is equated only with the pronoun he (him):
If you help a person who is in shock
1. Lay him flat on his back.
2. Raise his feet.
3. Cover him blanket to keep him warm.
4. Give him a warm drink.
5. Keep him quiet.

After these incursions into the domains of pragmatics and lexical semantics, let us now sum up what makes the conceptualization of natural gender, i.e. what we see as inherently linked with natural gender. The following list is not necessarily exhaustive. Natural gender involves a two-term opposition (either masculine vs. feminine or human vs. not human); it is an objective piece of information; it is not supposed to be predicated of a referent; it is stable (i.e. it does not change), this last characteristic being the reason why it is taken for granted. One may also add that natural gender is not gradable – I will come back to this characteristic. Note that what constitutes the concept may be a simplified version of what we experiment in our daily lives. Although in real life gender may, in some rare cases, change (some individuals may switch from male to female or vice-versa), the most usual and typical (i.e. entrenched) situation is that gender does not change (there is no switching between human and not human), and that is what is selected in the concept.

I will now address the question of the link between natural and grammatical gender. How can the conceptualization of natural gender account for some aspects of grammatical gender.