diff --git a/types.go b/types.go
index ec75ffe..0828a0b 100644
--- a/types.go
+++ b/types.go
@@ -1543,7 +1543,7 @@ type PollOption struct {
 	// Currently, only custom emoji entities are allowed in poll option texts
 	//
 	// optional
-	TextEntities []MessageEntity `json:"text_entities"`
+	TextEntities []MessageEntity `json:"text_entities,omitempty"`
 	// VoterCount is the number of users that voted for this option
 	VoterCount int `json:"voter_count"`
 }
@@ -1556,12 +1556,12 @@ type InputPollOption struct {
 	// Currently, only custom emoji entities are allowed
 	//
 	// optional
-	TextParseMode string `json:"text_parse_mode"`
+	TextParseMode string `json:"text_parse_mode,omitempty"`
 	// A JSON-serialized list of special entities that appear in the poll option text.
 	// It can be specified instead of text_parse_mode
 	//
 	// optional
-	TextEntities []MessageEntity `json:"text_entities"`
+	TextEntities []MessageEntity `json:"text_entities,omitempty"`
 }
 
 // PollAnswer represents an answer of a user in a non-anonymous poll.
@@ -1593,7 +1593,7 @@ type Poll struct {
 	// Currently, only custom emoji entities are allowed in poll questions
 	//
 	// optional
-	QuestionEntities []MessageEntity `json:"question_entities"`
+	QuestionEntities []MessageEntity `json:"question_entities,omitempty"`
 	// Options is the list of poll options
 	Options []PollOption `json:"options"`
 	// TotalVoterCount is the total numbers of users who voted in the poll
@@ -1733,14 +1733,19 @@ type BackgroundFill struct {
 	//  - gradient
 	//  - freeform_gradient
 	Type string `json:"type"`
+	// BackgroundFillSolid only.
 	// The color of the background fill in the RGB24 format
 	Color int `json:"color"`
+	// BackgroundFillGradient only.
 	// Top color of the gradient in the RGB24 format
 	TopColor int `json:"top_color"`
+	// BackgroundFillGradient only.
 	// Bottom color of the gradient in the RGB24 format
 	BottomColor int `json:"bottom_color"`
+	// BackgroundFillGradient only.
 	// Clockwise rotation angle of the background fill in degrees; 0-359
 	RotationAngle int `json:"rotation_angle"`
+	// BackgroundFillFreeformGradient only.
 	// A list of the 3 or 4 base colors that are used to generate the freeform gradient in the RGB24 format
 	Colors []int `json:"colors"`
 }
@@ -1758,27 +1763,35 @@ type BackgroundType struct {
 	//  - pattern
 	//  - chat_theme
 	Type string `json:"type"`
+	// BackgroundTypeFill and BackgroundTypePattern only.
 	// The background fill or fill that is combined with the pattern
 	Fill BackgroundFill `json:"fill"`
+	// BackgroundTypeFill and BackgroundTypeWallpaper only.
 	// Dimming of the background in dark themes, as a percentage; 0-100
 	DarkThemeDimming int `json:"dark_theme_dimming"`
+	// BackgroundTypeWallpaper and BackgroundTypePattern only.
 	// Document with the wallpaper / pattern
 	Document Document `json:"document"`
+	// BackgroundTypeWallpaper only.
 	// True, if the wallpaper is downscaled to fit in a 450x450 square and then box-blurred with radius 12
 	//
 	// optional
-	IsBlurred bool `json:"is_blurred"`
+	IsBlurred bool `json:"is_blurred,omitempty"`
+	// BackgroundTypeWallpaper and BackgroundTypePattern only.
 	// True, if the background moves slightly when the device is tilted
 	//
 	// optional
-	IsMoving bool `json:"is_moving"`
+	IsMoving bool `json:"is_moving,omitempty"`
+	// BackgroundTypePattern only.
 	// Intensity of the pattern when it is shown above the filled background; 0-100
 	Intensity int `json:"intensity"`
+	// BackgroundTypePattern only.
 	// True, if the background fill must be applied only to the pattern itself.
 	// All other pixels are black in this case. For dark themes only
 	//
 	// optional
-	IsInverted bool `json:"is_inverted"`
+	IsInverted bool `json:"is_inverted,omitempty"`
+	// BackgroundTypeChatTheme only.
 	// Name of the chat theme, which is usually an emoji
 	ThemeName string `json:"theme_name"`
 }