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【多选题】
激光通信的优势在于（）。A.
频率成份单一
B.
方向性极好
C.
发散角小
D.
能够避免同频干扰和邻频干扰
E.
传输距离远
F.
能量高
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举一反三
【简答题】阅读理解。 Once there was a clever farmer. Though he was poor, he decided one day to take the king a roast goose (烤鹅) as a present. He had not had 1 to eat that day, and soon the 2 of the roast goose becam...
【单选题】Though he had been trained for three months, ________he didn’t pass the exam.
A.
but
B.
and
C.
still
D.
so
【简答题】汤姆打碎了盘子还是金表 It was Sunday and Tom was staying at home. After breakfast he went out into the garden and played quietly by himself. There were no kids around and he was used to(1) playing alone quietly....
【简答题】nevertheless(2题) however(2题) though(1题) but(2题) nonetheless(1题) 1. He wanted to take no risks, (第1空) small. 2. The book is too long (第2空) , (第3空) , informative and entertaining. 3. I want to tr...
【简答题】He promised me a letter; he ought to _____it days ago. A. be written B. have written C. be writing D. write 2. Peter couldn’t have written to me, or I _____received his letter. A. had B. have...
【简答题】An elderly woman died yesterday after being knocked down by a motorist. The driver had _ 1 _ no attempt to brake (刹车). When a policeman asked him, a man of 69, to read the number plate of a car parked...
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