What common syntax errors can lead to a "parse error: syntax error" in PHP code?

A common syntax error that can lead to a "parse error: syntax error" in PHP code is missing or mismatched parentheses, brackets, or curly braces. This error occurs when the opening and closing symbols do not match up correctly. To solve this issue, carefully check your code for any missing or misplaced parentheses, brackets, or curly braces.

// Incorrect code with missing parentheses
if ($x > 5 {
    echo "x is greater than 5";
}

// Corrected code with matching parentheses
if ($x > 5) {
    echo "x is greater than 5";
}