src/reducers/AddNewsReducer.js

-import { WRITE_NEWS, CLEAR_WRITE } from '../actions/types';
+import { CLEAR_WRITE, WRITE_NEWS } from '../actions/types';
 
 const INITIAL_STATE = { title: '', text: '' };
 

src/reducers/AddTaskReducer.js

+import { CLEAR_WRITE, WRITE_TASK, WRITE_TASK_DEADLINE } from '../actions/types';
+
+const INITIAL_STATE = { title: '', text: '', deadline: '' };
+
+export default (state = INITIAL_STATE, action) => {
+  switch (action.type) {
+    case WRITE_TASK:
+      return { ...state, [action.target]: action.payload };
+    case WRITE_TASK_DEADLINE:
+      return { ...state, [action.target]: action.payload };
+    case CLEAR_WRITE:
+      return INITIAL_STATE;
+    default:
+      return state;
+  }
+};