diff --git a/internal/bill/domain.go b/internal/bill/domain.go
index 9632f1a..c4e4175 100644
--- a/internal/bill/domain.go
+++ b/internal/bill/domain.go
@@ -8,11 +8,37 @@ import (
 // Bill represents 'bills' object.
 type Bill struct {
 	gorm.Model
-	Type    string
-	Date    string
+	Year    int
+	Month   int
+	Day     int
 	Money   float64
-	Class   string
+	Label   string
 	Options string
+	Type    string
+}
+
+type BillDTO struct {
+	ID      int     `json:"id"`
+	Year    int     `json:"year"`
+	Month   int     `json:"month"`
+	Day     int     `json:"day"`
+	Money   float64 `json:"money"`
+	Label   string  `json:"label"`
+	Options string  `json:"options"`
+	Type    string  `json:"type"`
+}
+
+func (b *Bill) Dto() BillDTO {
+	return BillDTO{
+		ID:      int(b.ID),
+		Year:    b.Year,
+		Month:   b.Month,
+		Day:     b.Day,
+		Money:   b.Money,
+		Label:   b.Label,
+		Options: b.Options,
+		Type:    b.Type,
+	}
 }
 
 // BDate 用于判断获取bill的时间范围
@@ -34,8 +60,8 @@ type BillRepository interface {
 }
 
 type BillService interface {
-	GetBills(ctx context.Context, date BDate) ([]Bill, error)
-	GetBillByID(ctx context.Context, id int) (*Bill, error)
+	GetBills(ctx context.Context, date BDate) ([]interface{}, error)
+	GetBillByID(ctx context.Context, id int) (interface{}, error)
 	CreateBill(ctx context.Context, bill *Bill) error
 	UpdateBill(ctx context.Context, bill *Bill) error
 	DeleteBill(ctx context.Context, id int) error