每2人住一间房，旅游团17人要住（　　）间房．

如图，一渔船由西往东航行，在A点测得海岛C位于北偏东60°的方向，前进20海里到达B点，此时，测得海岛C位于北偏东30°的方向，则海岛C到航线AB的距离CD等于____海里．

人体呼吸器官由哪些组成？作用是什么？

用所给词的适当形式填空

（1）Autumn is a____(wonder)season.

（2）We all hope____(have)a long holiday.

（3）I____(buy)a new car the day before yesterday.

（4）I like doing some____(shop)with my parents.

（5）He did some____(read)last night.