At school, some students are active ______ some are shy, yet they can be good friends with one another.

 Yunnan is       colorful     millions of people come to enjoy themselves every year.                                                                      

Work hard, ___________ you’ll get good grades.

—_____ does your brother go online?  —Let me see. Maybe two or three times a week.

—Do you like math?—Yes, it’s difficult ________ really interesting.