How to check for a variable that contains consecutive letters, all uppercase or all lowercase

How to find a variable that contains consecutive letters, all uppercase or lowercase
$str = "Ads put the home on a LSD to lose weight fell in love with the Sdafgdsfghfdghjgfjghjgfhj Fonsada wasted scholar-bureaucrat by the law 48955235 Saada waste scattered local teacher place immediately understand";
$p = "/\d{5}/i";

Preg_match_all ($p, $str, $result);
Var_dump ($result);
The above can be found in 5 consecutive digits, if changed to a letter, how to write the regular, see the letter (all lowercase or all uppercase consecutive) number of digits Unlimited


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/[a-z]| [a-z]+/or/[a-z]/i
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Correction:/[a-z]+/i
Above is case insensitive
/[a-z]+/
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$p = "/[a-z]{5,}/i";
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Wrong. Try it this way.
$p = "/[a-z]{5,}| [A-z] {5,}/";
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Landlord's "Number of unlimited" is what mean, can be 0, that is:/[a-z]*/
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Full capitalization or full lowercase is:/([a-z]*) | ([a-z]*)/
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View letters (all lowercase or all uppercase consecutive) number of digits
It's all lowercase/[a-z]+/.
All caps,/[a-z]+/.

Not sure is wrong, so can't be *

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$p = "/[a-z]+/";
A-Z Match case in English
+ occurrences greater than or equal to 1 times

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