Google Translate can be integrated directly into Excel using an add-in developed by Google. To install it, go to the tab > "Insert" in the Excel ribbon, then > "Get add-ins" and search for "Google Translate". Once the add-in has been installed, select the cell to be translated, go to the "Add-ins" tab in the Excel ribbon > "Google Translate", select the source and target languages, then click > "Translate".