are the blue hats on sale? — They are on sale for 100 dollars.[ ]

Do you play _________ piano in your free time? —– No, I like sports. I often play ________ soccer with my classmates.

Our Maths teacher always makes his class _____ . And we’re never tired of his class.

His friends go to Beidaihe by train vacation every year.[ ]

The 16th ______ Games will be held in Guangzhou, we’ll watch the ______ opening ceremony on TV on November 12th.