diff --git "a/\345\210\230\344\275\263\344\270\275/20220516-\346\225\260\347\273\204\344\275\234\344\270\232.md" "b/\345\210\230\344\275\263\344\270\275/20220516-\346\225\260\347\273\204\344\275\234\344\270\232.md"
new file mode 100644
index 0000000000000000000000000000000000000000..5f24cb233ae9aac650c9ecbf95eb533e22b0ec46
--- /dev/null
+++ "b/\345\210\230\344\275\263\344\270\275/20220516-\346\225\260\347\273\204\344\275\234\344\270\232.md"
@@ -0,0 +1,56 @@
+# 作业
+
+```php
+";
+
+//2、 至少对3个字符串函数进行应用
+$str= " hello boy ";
+echo strtoupper($str)."
";
+echo trim($str)."
";
+echo ltrim($str);
+echo "