Remember the ubuntu installation process:

's first steps similar to 16.04 (18.04), after loading EasyBCD guide cannot enter, and went black grub (interviewed a variety of code to nothing in the world) first so fn + f12 into ubuntu trial mode, the terminal to download... . (can't find the code for a while, and the result is produced on the ubuntu system choice of interface),

Deleting the wrong version (18.04), the computer for the legacy boot, uninstall Ubuntu time legacy use RAMFIX (but only supports doing previous versions), UEFI boot mode with UEFIeasy deleted,

Delete failed, just under 90 g 16.04, as a result, when installation, the system automatically check out with 18.04 and uninstall success, but into the ubuntu pop-up window shows "lower image... (English) ", after the search, the boot interface into the ubuntu advanced options, select the last one, and then choose to resume (every time so, other haven't find a solution),

Ubuntu16.04 installation: https://blog.csdn.net/flyyufenfei/article/details/79187656

To find Ubuntu16.04 WIFI is disabled: https://blog.csdn.net/pkueecser/article/details/7594989, effective measurement,

Finally, mostly normal, occasional ubuntu images abnormal card, and won't open the Windows, restart,

Terminal input password is not displayed, ros in losing roscore first, open a new terminal again!