Creating Adjectives.

Version 2
In previous posts I have touched on the subject that certain nouns and verbs will require more than one adjective form. It would be very nice if one could simply produce a set of rules that says “adjectives with this suffix in English become this word form in Diinlang”. Unfortunately, suffixes in English are far too diverse and inconsistent for this to be practical. Hogben gives some insights into the problems inherent in such an approach.
As Hogden notes, many of the more modern adjectives have been created by using a noun or verb-derived noun. In Diinlang the progressive/ continuous form of the verb and the perfect form have both been designed so they can be used as single word nouns or adjectives. The progressive/ continuous form for the verb “VERB” would be “isVERB”. The perfect form would be “dunVERB”. As in English the progressive/ continuous form may be considered to be active in nature and the perfect passive in nature. Therefore rather than the perfect form we use the passive, “geVERB” form. From the verb root we can also create animate and inanimate agent nouns: VERBze and VERBit. These may also provide adjectives, as potentially the derived patient noun, VERBge.
A large number of adjectives for Diinlang can be created from verbs and nouns by using the active or passive participle. To do this it is necessary to determine if the adjective would have an active or a passive role in a noun phrase using it. As Hogben notes, an “-ing” or “-ed/ en” ending in English as they are used is not always reliable. Replacing the adjective in English with an “-ing” or “-ed” form can give a hint to whether it is passive or active. A “scary man” can be termed a “scaring man” so this is active. A “scared man” is not the same as a “scaring man”. “Scared man” is passive.
If the adjective describes something that the noun is feeling, experiencing or doing then it is active and the “isVERB” form should be used.
If the noun is the recipient of the effect the adjective describes the passive (“geVERB”) form is used. i.e. something is “being/ getting/ got done” to the noun or the noun has that status or state.  
The above system will deal with the majority of adjective (or adverb) generation for Diinlang. A smaller collection of words may require different solutions.
Firstly, there are the words whose primary function is adjectival. These include words for colour or size, for example. The above protocol can be used to modify these words if necessary. A “blue compound” can become a “bluing compound” or a “blued compound” by adding a “is-” or “ge-” prefix to the word selected for “blue”. An adjective can be converted to a concrete noun by adding “-it” to make it into an inanimate agent noun. An abstract noun can be created by adding the suffix “-ia”. Hence the Diinlang word for “blueness” would end in “-ia”.
Many of the variations of words will be created by compounding words rather than using a long list of empty suffixes. Many English adjectives that end in –able or –ble therefore are a compound with “zhan” (to be able). Words for edible, readable, drinkable may all be compounds of “-zhan”. The potential passiveness of some meanings may need to be addressed.
Words that denote something is caused or evoked will also be compounds, probably using the word “fiy” for to make or construct. Thus to words for “weaponize” or “liquidize” will be closer in sound to their alternative of “weaponify” and “liquefy”. To change something into water would be to “kwafiy”.
Another compound will be created to mean “becoming” or “beginning”.
English words that use the suffix “–less” in the sense of not having a property will most likely be constructed as a compound with the word “zero”, although for some senses “no” or “non-“ might be used instead.  The opposite of “-less” words in English often have the suffix “-ful” in the sense of completely having a property. Logic suggests Diinlang use a compound with a word for “total” for this sense. Terms such as “handful” and “cupful” can be translated literally.
A large variety of English suffixes indicate that the subject contains the quality described. Logically words such as “sugary”, “hairy” might be translated into compounds with the word “kom” (“with”), possibly combined with a comparative. >
A potentially useful suffix would be “-yi”, the equivalent of “-y”, “-ie”, “-e” and “-ey” in English. Creates the meaning of “having the quality of” when used with nouns and adjectives and “inclined to” on verbs. Examples in English include slimy, baggy, runny etc. “-li” might be used to make adverbs and adjectives of manner.
Saying that something is “wooden” or “metallic” is redundant when one can simply use “wood” or “metal” as an adjective. Metallic also has the sense that something resembles metal in some respects but is not necessarily metal. Compound words that indicate varying degrees of resemblance will also be needed. “-ish” and “-oid” are potential candidates already in wide use in many other languages. The word “iso” for “same” may also see use.
There are still some words that do not fit into the categories above. Many adjectives have a meaning of “pertaining to” or “to do with” without denoting a particularly active or passive meaning. For such adjectives the suffix “-al” can be used, although it can be regarded as optional and can be omitted if the word will not be confused with a noun. Possibly the ending “-an” would be used for adjectives relating to space and time, such as the names of nationalities.