判断题 Short message communication service is a technical breakthrough unique to Beidou system and not possessed by the GPS system.

单选题 How many Chinese charactes at most can be sent through Beidou?

单选题 We're seeing that emerge in ______.

单选题 This ______ has now claimed hundreds of lives.

单选题 Other devices ______ the health of patients.

单选题 Which of the following is not Beidou's application aera?

单选题 The______ is difficult for foreigners to learn.

单选题 I'll send you a text ______.

单选题 ______ is the longerst river in China.