On a most fundamental level, Thai grammar is extremely simple, especially in comparison with more “complicated” European languages like French or German. For example, verbs do not inflect in Thai, but each lexical unit (or word) always stays the same. There is no declination either, no plural forms of nouns and no conjugation of verbs. Moreover, no distinctive verb forms are being used in order to signalize past tense, present, and future.
Whereas in English, for example, the verb “to have”, depending on the speaker, time etc. is modified each time it’s being used in a different context (I have, she has, we had etc.), the equivalent Thai verb mee (“to have”) always stays mee, regardless of which context it is being used in.
There is no morphological distinction between classes of words such as nouns, verbs, adjectives or adverbs. Instead of different word classes, certain combinations of words define the current usage of a word. For example, by simply doubling the adjective reo (“quick”) it becomes the corresponding adverb (reo reo = “quickly”). Likewise, the prefix kwaam in front of an adjective turns it into a noun (e.g. kwaam reo = “speed”).
There are no articles in Thai language either, and much less prepositions are being used.