What are common causes of "unexpected T_String" errors in PHP code?

Common causes of "unexpected T_String" errors in PHP code include missing or mismatched quotes, semicolons, or parentheses in a string or statement. To solve this issue, carefully check the syntax of your code and ensure that all quotes, semicolons, and parentheses are properly matched and closed.

// Incorrect code causing unexpected T_String error
echo "Hello World';
```

```php
// Corrected code with proper quotes
echo "Hello World";