X射线的发现者是
A. 伦琴
B. 居里夫人
C. 诺贝尔
D. 门捷列夫
“放射性”概念的提出者是
A. 伦琴
B. 居里夫人
C. 诺贝尔
D. 门捷列夫
In the video ,we can hear My stomach is rumbling.Which word has the similar meaning?( )
A. ache
B. hungry
C. uncomfortable
D. grumble
What does “I have a tight schedule today.”mean?( )
A. I am free today.
B. I am pretty busy today.
C. I have to work today.
D. I have to go to school today.
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