diff --git a/backbone/backbone.d.ts b/backbone/backbone.d.ts
index 0c688f3084..04bee0f5d7 100644
--- a/backbone/backbone.d.ts
+++ b/backbone/backbone.d.ts
@@ -11,14 +11,14 @@ declare module Backbone {
     export interface AddOptions extends Silenceable {
         at: number;
     }
-    
+
     export interface CreateOptions extends Silenceable {
         wait: bool;
     }
-    
+
     export interface HistoryOptions extends Silenceable {
-        pushState: bool;
-        root: string;
+        pushState?: bool;
+        root?: string;
     }
 
     export interface NavigateOptions {
@@ -30,7 +30,7 @@ declare module Backbone {
     }
 
     export interface Silenceable {
-        silent: bool;
+        silent?: bool;
     }
 
     interface on { (eventName: string, callback: (...args: any[]) => void, context?: any): any; }
@@ -68,8 +68,8 @@ declare module Backbone {
         constructor (attributes?: any, options?: any);
         initialize(attributes?: any);
 
-        get(attributeName: string): any;
-        set(attributeName: string, value: any, options?: Silenceable);
+        get(attributeName: string): any;
+        set(attributeName: string, value: any, options?: Silenceable);
         set(obj: any, options?: Silenceable);
 
         change();