Yes, you can. If you can't remember Operator Precedence and Associativity, then just add more parentheses so that there is no doubt.

if ( (($a == 1) && ($b < 2)) && (($d < 4) && ($e >= 6)) ){ do somethin
+g ...
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The and operator can also be used in place of &&. and has lower precedence, but the following is the same as the above:

if ( (($a == 1) and ($b < 2)) and (($d < 4) and ($e >= 6)) ){ do somet
+hing ...
[download]