As to their morphological structure, prepositions fall under the follow­ing groups:

1) simple (in, on, at, for, with, etc.);

2) derivative (behind, below, across, along, etc.);

3) compound (inside, outside, within, without, notwithstanding, etc.);

4) composite (because of in front of, in accordance with, etc.).

Linguists who recognize that prepositions have lexical meanings di­vide this part of speech into groups united semantically. As a result, they distinguish between temporal, spatial, and grammatical (also referred to as logical) prepositions. This classification is deficient, since the majority of prepositions with long history have by now become polysemantic. As a result, one and the same preposition, depending on its distribution, may express any of the three types of relation: spatial (on the roof), temporal (on Monday), and logical (by, with, because of, etc.).

In the long run, for monosemantic prepositions, we may arrive at a semantic classification, whereas polysemantic prepositions will be classified according to their use. One must also keep in mind that spatial and temporal prepositions are contrasted with logical ones on the ground of transparency of their meaning. In addition, linguists state that logical prepositions are not semantically homogeneous: some of them are so abstract semantically that their meaning can hardly be defined (e.g. the prepositions of, to, by, with).

Some classifications are based on the type of relations between a prepo­sition and semantic meanings of the environment where it occurs. Preposi­tions are divided into a group with the left indicator of prepositional mean­ing (in the bag, with astonishment), with the right indicator (to accuse of smth, to object to smth) and a group of bilateral indication, where a preposi­tion can reveal its meaning both with the right and with the left indicator (to eat with, with a fork).