diff --git a/quill/quill-tests.ts b/quill/quill-tests.ts
index dbf8cb466f..5116ace525 100644
--- a/quill/quill-tests.ts
+++ b/quill/quill-tests.ts
@@ -69,11 +69,24 @@ function test_formatText2() {
     });
 }
 
-function test_formatLine() {
+function test_formatLine1() {
+    var quillEditor = new Quill('#editor');
+    quillEditor.formatLine(1, 3, 'api');
+}
+
+function test_formatLine2() {
     var quillEditor = new Quill('#editor');
     quillEditor.formatLine(1, 3, 'align', 'right');
 }
 
+function test_formatLine3() {
+    var quillEditor = new Quill('#editor');
+    quillEditor.formatLine(1, 3, {
+            'align': 'right',
+            'bold': false,
+        });
+}
+
 function test_insertEmbed() {
     var quillEditor = new Quill('#editor');
 
@@ -151,3 +164,11 @@ function test_addContainer()
     var quillEditor = new Quill('#editor');
     quillEditor.addContainer('ql-custom');
 }
+
+function test_on_EventType1(){
+    var quillEditor = new Quill('#editor');
+    quillEditor.on('text-change', (newDelta, oldDelta, source)=>{
+        // happened
+    });
+
+}
diff --git a/quill/quill.d.ts b/quill/quill.d.ts
index f1afd4c69f..2ec959ef99 100644
--- a/quill/quill.d.ts
+++ b/quill/quill.d.ts
@@ -5,6 +5,13 @@
 
 declare namespace QuillJS {
 
+    export interface QuillOptionsStatic {
+        debug?: string,
+        modules?: {[key: string]: any},
+        placeholder?: string,
+        readOnly?: boolean,
+        theme?: string
+    }
 
     export interface BoundsStatic {
         left: number,
@@ -28,52 +35,52 @@ declare namespace QuillJS {
     }
 
     export interface QuillStatic {
-        new (selector: string, options?: Object): QuillStatic;
+        new (selector: string, options?: QuillOptionsStatic): QuillStatic;
 
-        deleteText(start: number, end: number, source?: string): void;
+        deleteText(start: number, end: number, source?: "api"|"user"|"silent"): void;
         disable(): void;
         enable(enabled?: boolean): void;
         getContents(start?: number, end?: number): DeltaStatic;
         getLength(): number;
         getText(start?: number, end?: number): string;
-        insertEmbed(index: number, type: string, url: string, source?: string): void;
-        insertText(index: number, text: string, source?: string): void;
-        insertText(index: number, text: string, format: string, value: string, source?: string): void;
-        insertText(index: number, text: string, formats: any, source?: string): void;
+        insertEmbed(index: number, type: string, url: string, source?: "api"|"user"|"silent"): void;
+        insertText(index: number, text: string, source?: "api"|"user"|"silent"): void;
+        insertText(index: number, text: string, format: string, value: string, source?: "api"|"user"|"silent"): void;
+        insertText(index: number, text: string, formats: { [key: string] : any  }, source?: "api"|"user"|"silent"): void;
         pasteHTML(): string;
-        setContents(delta: DeltaStatic, source?: string): void;
-        setText(text: string, source?: string): void;
+        setContents(delta: DeltaStatic, source?: "api"|"user"|"silent"): void;
+        setText(text: string, source?: "api"|"user"|"silent"): void;
         update(source?: string): void;
-        updateContents(delta: DeltaStatic, source?: string): void;
+        updateContents(delta: DeltaStatic, source?: "api"|"user"|"silent"): void;
 
-        format(name: string, value: any, source?: string): void;
-        formatLine(index: number, length: number, source?: string): void;
-        formatLine(index: number, length: number, format: string, value: any, source?: string): void;
-        formatLine(index: number, length: number, formats: any, source?: string): void;
-        formatText(index: number, length: number, source?: string): void;
-        formatText(index: number, length: number, format: string, value: any, source?: string): void;
-        formatText(index: number, length: number, formats: any, source?: string): void;
-        getFormat(range?: RangeStatic): any;
-        getFormat(index: number, length?: number): any;
-        removeFormat(index: Number, length: Number, source?: String): void;
+        format(name: string, value: any, source?: "api"|"user"|"silent"): void;
+        formatLine(index: number, length: number, source?: "api"|"user"|"silent"): void;
+        formatLine(index: number, length: number, format: string, value: any, source?: "api"|"user"|"silent"): void;
+        formatLine(index: number, length: number, formats: { [key: string] : any  }, source?: "api"|"user"|"silent"): void;
+        formatText(index: number, length: number, source?: "api"|"user"|"silent"): void;
+        formatText(index: number, length: number, format: string, value: any, source?: "api"|"user"|"silent"): void;
+        formatText(index: number, length: number, formats: { [key: string] : any  }, source?: "api"|"user"|"silent"): void;
+        getFormat(range?: RangeStatic): {[key: string]: any};
+        getFormat(index: number, length?: number): {[key: string]: any};
+        removeFormat(index: Number, length: Number, source?: "api"|"user"|"silent"): void;
 
         blur(): void;
         focus(): void;
         getBounds(index: number, length?: number): BoundsStatic;
         getSelection(focus?: boolean): RangeStatic;
         hasFocus(): boolean;
-        setSelection(index: number, length: number, source?: string): void;
-        setSelection(range: RangeStatic, source?: string): void;
+        setSelection(index: number, length: number, source?: "api"|"user"|"silent"): void;
+        setSelection(range: RangeStatic, source?: "api"|"user"|"silent"): void;
 
-        on(eventName: string, callback: (delta: DeltaStatic, oldContents: DeltaStatic, source: String) => void): QuillStatic;
-        on(eventName: string, callback: (range: RangeStatic, oldRange: RangeStatic, source: String) => void): QuillStatic;
+        on(eventName: string, callback: (<T>(delta: T, oldContents: T, source: string) => void) |
+                                            ((name: string, ...args) => void )): QuillStatic;
         once(eventName: string, callback: (delta: DeltaStatic, source: string) => void): QuillStatic;
         off(eventName: string, callback: (delta: DeltaStatic, source: string) => void): QuillStatic;
 
         debug(level: string): void;
         import(path: string): any;
         register(path: string, def: any, suppressWarning?: boolean): void;
-        register(defs: any, suppressWarning?: boolean): void;
+        register(defs: { [key: string] : any  }, suppressWarning?: boolean): void;
         addContainer(className: string, refNode?: any): any;
         getModule(name: string): any
     }