Correct translation of dates in wordpress?

Question

Machine translation from one language to another

Good afternoon, 3 days I've been struggling with dates on wordpress in the format ago
There is a jamb in the translation (declensions are not taken into account)
In the singular - month (month)
In the plural - months (months)
There is not enough rule for the number of months 2,3,4 ,22 etc.
How it is displayed:

Who rules?) Plugins like RussianDate do not help.
in POedit, this is how this system is implemented in the engine itself (not in the topic)

And like this in the topic:

Answer 1

Decision:

<?php
function declOfNum($number, $titles) {
$cases = array (2, 0, 1, 1, 1, 2);
return $titles[ ($number%100 > 4 && $number %100 < 20) ? 2 : $cases[min($number%10, 5)] ]; 
}
echo declOfNum($number, array('месяц', 'месяца', 'месяцев'));
// вместо $number выводи the_time(); или типо того
?>

For check:

<?php
echo '1 ' . declOfNum(1, array('месяц', 'месяца', 'месяцев')) . '<br/>';
echo '2 ' . declOfNum(2, array('месяц', 'месяца', 'месяцев')) . '<br/>';
echo '5 ' . declOfNum(5, array('месяц', 'месяца', 'месяцев')) . '<br/>';
?>