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【单选题】
下列关于光纤光栅的说法，正确的选项是？A.
第一根光纤光栅是由K. O. Hill等人利用相位掩模技术进行刻写的
B.
Bragg 光纤光栅的光学特性是由向前传输的导模与包层模耦合的结果
C.
啁啾光纤光栅是用来消除旁瓣
D.
长周期光纤光栅透射谱谐振波长与包层周围介质的折射率有关
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【简答题】到处走走;四处行走;观光;游览
【判断题】Read the statements. Then listen to the news and check the True (T) or False (F) statements. There are few measures we can adopt to protect ourselves and others from getting the New Coronavirus.
A.
正确
B.
错误
【多选题】part5.mp4 Are they ambitions? Look at the people below and read the statements. Then watch Part 5 of the podcast and check the true statements.
A.
The first people likes to take control and make things happen for himself.
B.
The second people is ambitious, but she hasn't realized her dream.
C.
The third people is ambitious in developing other people's art.
D.
The last people wants to get a high salary and live in a nice house.
【简答题】因此,于是 adv.
【判断题】Watch the video. Read the statements. Choose T or F. 1. Dave never gets stressed.
A.
正确
B.
错误
【简答题】从某种意义上说,在布热金卡,最可怕的事情是这里居然阳光明媚温暖,一行行白杨树婆娑起舞,在大门附近的草地上,还有儿童在追逐游戏。 这真像一场噩梦,一切都可怕地颠倒了。在布热金卡,本来不该有阳光照耀,不该有光亮,不该有碧绿的草地,不该有孩子们的嬉笑。布热金卡应当是个永远没有阳光、百花永远凋谢的地方,因为这里曾经是。 ...... 十四年前,最后一批囚徒被剥光衣服,在军犬和武装土兵的押送下走进毒...
【判断题】Read the statements. Then listen to the news and check the True (T) or False (F) statements. 1. There are few measures we can adopt to protect ourselves and others from getting the New Coronavirus.
A.
正确
B.
错误
【简答题】U1-Sharing-2.wmv What are they learning at the moment? Look at the people below and read the statements. Then watch Part 2 of the podcast and check the true statements.
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