The adjective interstitial pertains to a narrow opening or a crack between two things.
Subsistence is the means someone has to support their existence, usually referring to food and shelter.
When you persist in doing something, you keep on or continue doing it faithfully.
An inconsistency is something that does not quite fit with the rest of the members of its group because it is irregular or self-contradictory.
When you assist another person, you help them do something.
When you resist something, you try to stop it from happening by fighting or working against it.
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