Most Mandarin varieties have four tones. The final stops of Middle Chinese have disappeared in most of these varieties, but some have merged them as a final glottal stop. Many Mandarin varieties, including the Beijing dialect, retain retroflex initial consonants, which have been lost in southern dialect groups.
explorer.exe is a system process that is needed for your PC to work properly. It should not be removed. Check your system now to identify unused processes that are slowing down your computer. The explorer.exe file is an executable file for Windows Explorer.
Internet Explorer is a Web browser that allows you to view files on the Internet. It also gives you the ability to upload files onto an Internet server. Uploading a file is the process of copying a file from your hard drive to the hard drive of a computer on the Web.