diff --git a/src/mechanize/form.cr b/src/mechanize/form.cr
index 86da5bb..9be8082 100644
--- a/src/mechanize/form.cr
+++ b/src/mechanize/form.cr
@@ -8,14 +8,20 @@ require "./form/button"
 require "./form/select_list"
 require "./utils/element_matcher"
 
+# THis class represents the form tag of html.
 class MechanizeCr::Form
   include MechanizeCr::ElementMatcher
 
   getter node : Node | Lexbor::Node
+  # returns an array of `MechanizeCr::FormContent::Field` in the form.
   getter fields : Array(FormContent::Field)
+  # returns an array of input tags whose type is checkbox in the form.
   getter checkboxes : Array(FormContent::CheckBox)
+  # returns an array of input tags whose type is radio in the form.
   getter radiobuttons : Array(FormContent::RadioButton)
+  # returns an array of input tags whose type is select in the form.
   getter selectboxes : Array(FormContent::MultiSelectList)
+  # returns an array of button tags and input tag whose type is button,submit,reset,image.
   getter buttons : Array(FormContent::Button)
   getter enctype : String
   getter method : String
diff --git a/src/mechanize/utils/element_matcher.cr b/src/mechanize/utils/element_matcher.cr
index b1a2e5f..0172f92 100644
--- a/src/mechanize/utils/element_matcher.cr
+++ b/src/mechanize/utils/element_matcher.cr
@@ -6,11 +6,26 @@ module MechanizeCr::ElementMatcher
     # Examples
     # ```
     # # if you specify String like "foo", it searches form which name is "foo".
-    # # like <{{ singular.id }} name="foo"></form>
+    {% if ["form", "button"].includes?("#{singular.id}") %}
+      # # like <{{ singular.id }} name="foo"></{{ singular.id }}>
+    {% elsif "#{singular.id}" == "field" %}
+    # # like <input name="foo"></input>
+    {% elsif "#{singular.id}" == "radiobutton" %}
+    # # like <input type="radio" name="foo"></input>
+    {% else %}
+    # # like <input type="{{ singular.id }}" name="foo"></input>
+    {% end %}
     # page.{{ plural.id }}_with("foo")
-    # 
     # # you can also specify tag's attribute and its' value by NamedTuple or Hash(String, String).
-    # ex) &lt;{{ singular.id }} class="foo"&gt;&lt;/form&gt;
+    {% if ["form", "button"].includes?("#{singular.id}") %}
+    # # ex) <{{ singular.id }} class="foo"></{{ singular.id }}>
+    {% elsif "#{singular.id}" == "field" %}
+    # # ex) <input class="foo"></input>
+    {% elsif "#{singular.id}" == "radiobutton" %}
+    # # ex) <input type="radio" class="foo"></input>
+    {% else %}
+    # # ex) <input type="{{ singular.id }}" class="foo"></input>
+    {% end %}
     # page.{{ plural.id }}_with("class" => "foo")
     # page.{{ plural.id }}_with(class: "foo")
     # ```