diff --git a/QUICK_START.md b/QUICK_START.md
index e69de29..f42ca2a 100644
--- a/QUICK_START.md
+++ b/QUICK_START.md
@@ -0,0 +1,17 @@
+# engine process [ProcessKey(const KeyEvent & key_event)](https://github.com/rime/librime/blob/99e269c8eb251deddbad9b0d2c4d965b228f8006/src/rime/engine.cc#L95)
+```
+   foreach (processor in processors) {
+         ret= processor->ProcessKeyEvent(key_event)
+         if (ret== Rejected ) break;
+         if (ret== Accepted) return true
+         if (ret== Noop)  continue
+   }
+```
+## 當觸發 OnContextUpdate時 call [engine->Compose(Context* ctx)](https://github.com/rime/librime/blob/99e269c8eb251deddbad9b0d2c4d965b228f8006/src/rime/engine.cc#L159)
+* 處理 Segmentors 產生 [Composition](https://github.com/rime/librime/blob/99e269c8eb251deddbad9b0d2c4d965b228f8006/src/rime/composition.h#L21)
+  :public [Segmention](https://github.com/rime/librime/blob/99e269c8eb251deddbad9b0d2c4d965b228f8006/src/rime/segmentation.h#L59)
+  
+   Segmetion :public vector<[Segment](https://github.com/rime/librime/blob/99e269c8eb251deddbad9b0d2c4d965b228f8006/src/rime/segmentation.h#L18)>
+*  Composition comp 調出 segment 輪循 translator 
+  * translator 產生 translation 加入 segment.menu
+  * filter