Khēta is a subset of Kqān. The letter defines a point along the journey (symbolised in Yēta) from “A” to “B”.
Kha or more commonly “ka” is the beginning, the start of a journey or process.
Kho /ko is the goal or the end of a journey or process.
Khe /ke is the process of going from the beginning ka to the end ko, it’s also usually used to make a word a verb by turning into an “ing” verb.
Khei /kei is a secondary version of ke, less about a verb-maker and more about a position in that process. So if someone is working towards a goal, the “ing” verb is ke, if the person is on the path towards a goal (i.e. the linguistic inference is one of a non-specific point on the journey, rather than the actual doing it in the moment), the verb word will have kei in it.
Khii /kii and Khee /kee is a point in the middle. The use of kii over kee (which are pronounced the same way but the script diacritic is slightly different) depends on what kind of word is being used. One is the exact middle point in the journey, half way, and the other is the balance or a less scientifically perfect middle point.
Khai /kai is heading off the path in a direction that will be harmful, but the harm isn’t necessarily instant. As a verb, kai is used like something is headed in the wrong direction, but it’s possible to get back from it.
Khu /ku or koo is destruction, either moving in the completely wrong direction to get to the goal, or the “slippery slope” analogy, it’s also a point in a journey that may or may not destroy a person or situation or goal. So, if you’re talking about a person who was studying at university and fell into a drug-fuelled pit of despair and ended up having a breakdown, dropping out of university and being locked up… their coming to this point is ku, at the beginning of this process is kai (as in they’re heading in the wrong direction and really need to turn around or they’ll find themselves in a state of ku).
Generally these words are used to modify the meaning of other words, you can’t just say someone is in a state of ku or ka, without any modifyers to give context.