This is really a very simple task to perform. Remember you copy/pasted your document for checking. Well after you have finished making the changes all you need to do is to select the corrected document and copy/paste it back to the original document or save it as a new document. You can press the ‘Alt’ and ‘A’ keys to select the entire document and then copy it and paste it. However, in case you are saving it as a new document, do remember to name it properly so that you don’t get confused over which is the original and which is the corrected document.