在PHP中，可以使用多种方法进行字符串拼接，例如：
$string1 = "Hello";
$string2 = "World";
$combinedString = $string1 . $string2;
echo $combinedString; // 输出：HelloWorld
$string1 = "Hello";
$string2 = "World";
$combinedString = "$string1 $string2";
echo $combinedString; // 输出：Hello World
$string1 = "Hello";
$string2 = "World";
$combinedString = sprintf("%s %s", $string1, $string2);
echo $combinedString; // 输出：Hello World
$string1 = "Hello";
$string2 = "World";
$combinedString = concat($string1, $string2);
echo $combinedString; // 输出：HelloWorld
$stringArray = array("Hello", "World");
$combinedString = implode(" ", $stringArray);
echo $combinedString; // 输出：Hello World
