Microsoft ended support for Windows XP after April 8, which _______a major operating system for some Chinese computer users, and advised users to upgrade to Windows 8.1.

Up to now nobody          able to do this better than Charlie Chaplin.

---Play computer games again? There’re  two days left for the final exam! ---  _________you ________me? I’m too tired.

A new kind of drug ___ ___ to cure H7N9 bird flu by the scientists and they are hopeful that they will succeed in a couple of weeks. 

With Chang'e-3 successfully landing, China becomes the third country in the world that _______ on the moon.