初中英语词法填空题

What about 　　（practice）swimming this summer vacation？

His office is on the 　　（nine）floor of the tall building．

　　（Kate）grandparents usually have a walk around the lake in the morning．

We shouldn't waste water．Instead，we should 　　（节约） it．

The students are having a 　　（化学） class in the lab．

After working for several hours，he was t 　　and fell asleep soon．

Bill u 　　gets home at 6：00，but today he didn't get home until 7：00．

As we know，the m 　　goes round the earth．