These words pertain to the coming together of two or more people to accomplish a common task or pleasure. Share is the most general of these and is relatively informal. It may suggest the mere dividing of a portion or activity: sharing the profits; sharing the clean-up job to make it go faster. Often an added note of friendliness or warmth of feeling is present: sharing together an intense, unspoken sympathy. Join is like share in its informality; it may also stress good fellowship, especially in the sense of banding together for a common activity: neighbours who joined together in building a new house for the stricken family; spontaneously joining in the refrain of the song. This note of voluntary good will, however, may be totally absent: ordering them to join in digging the mass grave. The word often suggests the action of a person who becomes part of an already existing group: joining the excursion in Rome.

Participate , although considerably more formal, is like one aspect of join in specifically suggesting a joining or taking part in group activity: a shy student who only with difficulty learned to participate in the group discussions. The word implies a more active role than is necessarily the case with share or join : members who join the club and share in its ideals but still do not participate in the club’s activities. Partake is closer in meaning to share than to join or participate , although it is more formal than any of these words. It might, in fact, seem excessively formal in some cases. It suggests, most specifically, the receiving or taking of portions, especially of food: picnickers who unloaded their baskets and partook of a sumptuous though improvised feast. Sometimes the emphasis on food is felt so strongly that the word is used even for a person eating along: partaking of her solitary meal.

Commune is more like another aspect of share in emphasizing an intense give-and-take of quiet but warm feeling: communing together with wordless, unhurried glances. Like partake, the word may be used of a single person, in which case an internal dialogue may be suggested or a silent responsiveness to one’s surroundings, especially a natural setting: an old woman who sat communing with times long past; communing with nature. The last example is a stock phrase illustrating a certain preciousness that may be present when the word appears in this context.

Relates in current usage has become a fad word referring to interpersonal relationships: an autistic child completely unable to relate to anyone; people who relate to others only on the safest and most superficial of levels.