Investigating the characteristic features of the modern Turkish dialects in a comparative way recently became the most widely interested field among the Turkish studies. The reason for this is not only the tendency for convergence of the Turkic nations that split up for some reasons for a long time but also the eagerness of the linguists to prove to the linguistics science communities that the Turkic language family originates from the same roots and they exist as a whole. Hence, the investigation of the similarities and differences of the Modern Turkic Dialects in a comparative way and revealing the complete characteristic features of each dialect is a kind of necessity and an up-to-date concern. 

We argue that a comparative analysis of the conditional complex sentences in the modern Turkish and Azerbaijani languages, both of which are of the Southwest Turkic Dialects, will prove very useful for Turkish studies, considering the significance of comparative studies on the modern Turkic dialects and accents in regard to syntactical structure. There is a kind of sentence which is called the main sentence and it is formed by the means of the suffixes -sa, -se and they denote condition. And as the conditional part of the sentence in the Azerbaijani Turkic Language is not only used by the means of above-mentioned (-sa, -se) suffixes, but also by the other means, it leads us to focus on a huge difference between those two languages. 

In this paper, we shed light upon the views on the conditional complex sentences in grammar books by various researchers and proposed a variety of analyses based upon the comments of linguists on the conditional complex sentences in both languages. 

As a longer investigation we can come to the consideration shown as follow:

Sometimes the term of conditional clause can be confused with another term existing in the grammar of the Modern Turkish Language. But only the term “dependent (subordinate) conditional clauses” is used in the grammar of the Azerbaijan Turkic Language. 

According to the rules of the Modern Turkish grammar, the conditional clause is a kind of sentence which is formed by the means of the conditional suffixes -sa, -se and it is not used independently. On the other hand, it plays the role of adverbial modifier, object and subject of the main clause and complements other sentences by carrying the meanings of time, condition, cause and comparison. As well as it is the real compound sentence in the Modern Turkish language. 

According to the grammatical point of view in the Azerbaijani Turkic Language, the dependent compound sentences in the conditional sentences are divided into two parts. One of them is a kind of sentence in which the subordinate clauses come after the main clause and such sentences are widely used in the colloquial speech, but not in the literary speech. 

The second kind of sentences are widely used in the literary languages and they are divided into four parts with respect to their formation. The subordinate clause comes before the main clause in these sentences and they conjoin the main clause by means of conditional suffixes -sa, -se, intonation and the suffixes -a, -e denoting wish, and conditional conjunctions such as əgər (if), bir halda ki (in such as case), provided that (şimdi ki), supposing that etc). 

Unlike the grammar of the Turkish Turkic Language, in the grammar of Azerbaijan Turkic Language all sentences the predicate of which accepts the conditional suffixes -sa, -se is not considered conditional sentences. This is because, the conditional suffix -sa, se denotes other meanings rather than the condition and it can also be used in order to form the subject, predictive, objective clauses and the adverbial clauses of time, place, manner, quality and comparison. 

When we compare the grammatical rules of two neighbour countries, we should also consider the views about joining of conditional clauses in the Modern Turkish Language to the main clauses the syntactic function of which is subject, object, and adverbial modifier. 

According to Azerbaijani Turkic Language grammatical point of view, if the meaning is not changed while the sentences, the predicate of which is formed by the conditional suffix -sa, -se are used together with the conditional conjunctions and if it keeps its meaning then it is the conditional clause. If there is a change in the meaning in this kind of sentences, (sentences which predicate is formed using conditional suffixes) the predicate of which is formed by the means of conditional suffixes - sa, - se, then those sentences should be considered one of the above-mentioned subordinate clauses of complex sentences. Thus, using one of the conditional conjunctions strengthening the meaning of condition, the subordinate clauses the predicate of which is formed by the means of conditional suffixes -sa, -se determines whether they are conditional clauses or not. In the grammar of Modern Turkish Language, overemphasizing the role of the conditional suffixes -sa, -se and ignoring the role of the conditional conjunction among the means which are responsible for the forming of the conditional clauses, lead to the wrong classification of the sentences with respect to their meaning.