问题：
[单选,材料题] Who are the first to make the success of sit-in become true?
Who are the first to make the success of sit-in become true?
问题：
[单选] I _______ here two years ago．
I _______ here two years ago．
问题：
[单选] If you will do that, please take me into ________．
If you will do that, please take me into ________．
问题：
[单选,材料题] The reason why all the solar energy falling on the earth can’t be utilized is that ______．
The reason why all the solar energy falling on the earth can’t be utilized is that ______．
