In 1492, Columbus_______ on one of the Bahama Islands, but he mistook it for an island of India. A lands B landed C has landed D had landed
I’m very happy _________ a chance to visit your country.
Zhongguancun made __________ for him to realize his dream.
__________ the plan many times, but he still didn’t understand.
When he got home, he found the door _____, the window ______, the money and the necklace in the drawer _____.
_______ of my classmates could work out the maths problem because it was too difficult.