Update form.md

Added example for not using field()
http://www.yiiframework.com/forum/index.php/topic/49225-activeform-how-do-you-call-label-input-and-errors-individually/

docs/guide/form.md

@@ -88,3 +88,19 @@ customize the output, you can chain additional methods to this call:
 
 <?= $form->field($model, 'username')->textInput()->hint('Please enter your name')->label('Name') ?>
 ```
+
+This will create all the `<label>`, `<input>` and other tags according to the template defined by the form field.
+To add these tags yourself you can use the `Html` helper class. The following is equivalent to the code above:
+
+```php
+<?= Html::activeLabel($model, 'password'); ?>
+<?= Html::activePasswordInput($model, 'password'); ?>
+<?= Html::error($model, 'password'); ?>
+
+or
+
+<?= Html::activeLabel($model, 'username', ['label' => 'name']); ?>
+<?= Html::activeTextInput($model, 'username'); ?>
+<?= Html::error($model, 'username'); ?>
+<div class="hint-block">Please enter your name</div>
+```