In Russian, there is the spelling "alternating vowels." Words that obey this spelling rule cannot be verified by selecting cognate words, as is the case with unstressed root words. Their spelling sometimes depends on the consonant that follows the spelling, on the meaning of the word, or on the suffix used. Often these words cause difficulties for students, so the teacher needs to devote more time to studying the rule.
Roots in which there are alternating vowels, it is advisable to memorize and be able to distinguish them from other morphemes, similar in sound or spelling.
The spelling choices depend on several factors. In a dawn-, dawn- in an unstressed position (for example, a dawn), the letter A in the root is indicated on the letter, and in the opposite case (for example, dawns) - O. An exception in this case is the word zoryanka, which denotes the name of the bird.
Alternating vowels in the roots of mountains-, gar-, clan-, clone-, creat-, creature-: under stress is written A (tan, bow, creature), and in unstressed position O (sunbathe, bend, create). The exceptions are the words utensils, casseroles, burns. You also need to pay attention to the roots of melt and pilaf. In words with them, A is written in an unstressed case (float, fin, etc.). The exception is the nouns of the swimmer and swimmer. It is worth considering that in the word "quicksand" in the root is written "S" according to the sound.
Cases are common when alternating unstressed vowels depend on the consonant, which ends the morpheme. These are the words with the roots of lag, false, rast, ros, kas, kosn. For example, to assume - to suppose, to grow - grew, etc. There are exception words that need to be remembered. For example, Rostov, sprout, canopy, etc.
In some words, alternating vowels are selected depending on the meaning of the root. So, for example, the spelling in words with moc-, mak- is determined. If parts of speech are used in the meaning of "getting wet, letting fluid through," then use moc- (get wet in the rain, soak the laundry). When this root means "immerse in something", then mak- (dunk in water) is used.
This rule also applies to words that include parts such as equal and equal. "O" in unstressed position is written if the meaning is "smooth, even." Equal root is used when it means "equal, equal." For example: compare expression, smooth road.
In order for students to fix the spelling "alternating vowels in the root", exercises must be selected in such a way that they include words with different cases of spelling. It is important for children to periodically repeat the exceptions. There are not many of them for this spelling, which is why it's easy to remember. And with periodic consolidation of material for students it should not be difficult to determine which letter should be in the word.
It should be noted that some roots (ber-, bir-, der-, dir-, etc.) are written depending on the suffix that comes after it. In this case, if there is -a-, then the letter And is inserted, otherwise - E. For example, typing - takes, tearing apart - tearing, etc.