column mode in VIM

1. Move the cursor to the position where you want to operate.

2. Press CTRL + v into "visible" mode, select the column to operate on each row.
     select multiple coulmns using left/right arrow
     select multiple rows using up/down arrow
3. Enter  SHIFT + i (I) to insert the contents which you want to input.
4. Press ESC twice, the inserted contents appear in selected areas of the each row.