Unlike many languages, Hungarian has possessive suffixes. Instead of using two words to say "my car", Hungarian uses only one: auto'm. The word "auto'" means "car" and the suffix -m means "my". When the noun ends in a consonant, a linking vowel is required. The word "kertem" means "my garden". The word "kert" has a front vowel, so a front vowel is required in the suffix. However, if the noun consists of back vowels, a back vowel is required instead. This is illustrated by the word "ablakom" which means "my window". It consists of "ablak" (window) and the possessive suffix -om.
It is convenient to analyze the vowel of the possessive suffix as a linking vowel. The reason is that this eliminates the need to specify which vowel is underlying. With this analysis, it is sufficient to say that a front vowel is required with front vowel roots and a back vowel with back vowel roots.
In addition to possessive suffixes, Hungarian also has infixes. An infix is a morpheme which is placed between morphemes. For example, the Hungarian word for "my car" is "auto'm". This consists of the morpheme "auto" (car) followed by the possessive suffix -m. The Hungarian word for "my cars" is "auto'im". The -i- is an example of an infix. It is placed between the morpheme "auto'" and the morpheme -m. The English phrase "my cars" can be analyzed morphologically as my + car + s. In Hungarian this identical phrase is structured as follows: car + s + my. The two languages clearly use very different structures.
With nouns which end in a consonant, the linking vowel precedes the infix and the possessive suffix follows it. The word for "my cars" is "auto'im" and the word for "my houses" is "ha'zaim".
The linking vowel is necessary to preserve the syllable structure of "my house". In Hungarian this is "ha'zam" which is ha'z (house) + (a)m (my). The bracket serves to indicate that this is a linking vowel. By inserting this vowel, the word preserves a CV structure in the final syllable. The word "ha'zam" has the syllable structure CVC.VC. If it were not present, the word would have the syllable structure CVCC which is not possible in Hungarian.
In the case of "ha'zaim" (my houses), the linking vowel is not needed to preserve the syllable structure. Without the linking vowel, the result would be "ha'zim" which is an acceptable syllable structure in Hungarian. However, the linking vowel of the possessive suffix attached to the singular noun is preserved in the plural. The result is the syllable structure CV.CV.VC.
One may ask why "my houses" is "ha'zaim" rather than "ha'ziam". If it were "ha'ziam, the possessive suffix -am from "my house" would remain intact. However, there is a good explanation for "ha'zaim". With such a construction, it is clear that the noun is a plural. With a construction such as "haziam", the word could be interpreted as a singular noun plus the possessive suffix -am.
Another explanation can also be provided. With the structure "ha'zaim", the word for "my houses" has the same ending as the word for "my cars", "auto'im". Thus, the same sound sequence is preserved. The word "ha'zaim" can be analyzed as a word which consists of a root, a linking vowel, infix and possessive suffix. The use of a bracket is useful for indicating the linking vowel. The word "ha'zaim" can thus be shown as follows: ha'z + (a) + i + m.
The Hungarian language makes use of possessive suffixes. With roots that end in a consonant, a linking vowel is added to possessive suffixes which consist of a consonant. For forming the plural, i.e., "my cars", the infix -i' is used. Whether the noun ends in a vowel or a consonant, the structure which means my + plural noun such as "my cars" and "my houses" always ends with the sound sequence "im".