Chinese astronauts in Tiangong space station opened a science lecture on December 9th,2021 as they traveled around ___19___ Earth.

There ___20___（be）a lecture and some interesting activities on that exciting day.First,Zhai Zhigang,Wang Yaping and Ye Guangfu,all members of the Shenzhou XIII mission crew,greeted students,teachers and other participants as the lecture began at 3:40 pm.They then showed viewers the place ___21___ they live and work.The astronauts carried out experiments ___22___（show）interesting physical phenomena（現象）in space,___23___（include）'disappearing buoyancy（浮力）'and a'water ball'.At last,before the end of the livestreamed activities,they ___24___（happy）answered questions from students.___25___（million）of primary and middle school students across China watched the 60-minute televised event,which was the first lecture of the Tiangong Class,China's first extraterrestrial（地球大氣圈外的）lecture series to make students interested ___26___ space science.

The manned space agency said that more lectures would ___27___（hold）based on the country's manned spaceflights and would also be presented by some ____28____（profession）Chinese astronauts.Such activities are intended to spread knowledge about manned spaceflights for science among young people.

答案

1．A

2．D

3．C

4．B

5．B

6．A

7．B

8．A

9．participants

10．how

11．designed

12．conducted

13．who

14．weightless

15．the

16．will be held

17．activities

18．for

19．the

20．was

21．where

22．to show##showing

23．including

24．happily

25．Millions

26．in

27．be held

28．professional