The following produce equivalent results. $_ is the default if you don't specify a variable name.

@the_days = ('whatever','values','go','here');

foreach $eachday (@the_days) {
    print "$eachday\n";
}

for $eachday (@the_days) {
    print "$eachday\n";
}

for (@the_days) {
    print "$_\n";
}

print "$_\n" for @the_days;
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