Classification of complex sentences according to the type of subordinate clauses

One of the central topics discussed by linguists who study the structure of complex sentences is the problem of dependent clause classification.

There are recognized two main criteria for this classification, namely, functional and categorial [12].

The functional principle is based on the syntactic analogy of the parts of the simple sentence. In turn, this is based on an assumption that the structure of the simple sentence underpins that of the complex one. For truly, most of the subordinate clauses correspond and closely relate to the functional characteristics of the parts of the simple sentence. The given analogy is, of course, only partically accurate. There's a big difference in function of single word-unit and whole word-groups:

You can see my distracted attention. → You can see that my attention was distracted by some of my classmates.

Also there can be found certain types of clauses that do not easily correspond to any of the non-clausal language units [12]. Although still there does seem to be a general functional analogy between clausal and lexemic units of the sentence, which highlights the general similarity of their semantic purpose.

So, one might conclude that the functional classification of subordinate clauses based on the simple sentence-part analogy in, to some degree, justifiable and sustainable.

Now, as for the categorial principle, subordinate clauses аre grouped based on their nominative properties regardless of the immediate positional relations. According to this typology, the clauses correspond to parts of speech.

Some would argue that this classification is not justified because the clause in its essential and most general form represents an event, while a single lexime can only name some separate objects of reality.

A lexeme carries out purely nominative function. To the contrary, a clause, be it dependent or independent, can bear communicative function.

Even though most of the American grammar guidances use this classification, this approach may be called by some too simplistic.

On the other hand, this classification might be found quite plausible and helpful if we consider certain facts.

If we take into account the general nominative features of the subordinate clauses, there could be distinguished three categorial-semantic groups. The first one comprises the name of an event as a certain fact. Such subordinative clauses may be referred to as "substantive-nominal" [12]. To prove the assumption that they correspond by nature to their noun counterparts, let's provide some examples:

The teacher knew that the students were planning to play a joke on him. →The teacher knew about students' plan.

The second group of clauses (also called as «event-fact») characterizes some substantive entity. Such clauses can also be called "qualification-nominal"'[12]. As in the case with the first group of clauses, let's prove their relation to adjectives through the syntactic transformation:

The man who was almost dying stretched his hand in a distinct gesture.→The dying man stretched his hand in a distinct gesture.

Finally, talking about the third group of clauses, it can be noted that their event-nomination is expressed in relation to a quality of various actions that's why they are referred to as «adverbial». These clauses are best tested not by a replacement, but by a definitive transformation:

You'll get fluent if only you talk to native speakers. →You'll get fluent on a sole condition that you talk to native speakers.

When comparing the two classifications, some might see that they could be interpreted as contradicting each other. However, in reality they are mutually complementary, their respective bases being valid on different levels of analysis. The categorial features of clauses go together with their functional sentence-part features similar to the categorial features of lexemes going together with their functional characteristics as parts of the simple sentence.