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【多选题】
U xx +2u yy =f(x,y) 是:A.
型方程
B.
泊松方程
C.
线性方程
D.
椭圆型方程
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【单选题】________ information! I hear you have finished writing a ________ report.
A.
What an excited; seven thousand word’s
B.
What excited; seven thousand words
C.
What an exciting; seven-thousand-word
D.
What exciting; seven-thousand-word
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【单选题】听力原文：I signed up for a two-month-long course in writing, but Kate signed up for one that's only four weeks long. (26)
A.
Kate's course is only half as long as mine.
B.
Kate is enrolled in 4 courses.
C.
I signed a contract and went to work for two months.
D.
Kate signed a longer contract than I.
【单选题】March 16th, 2009 Dear Sir, In (141) with my agreement with your firm, I am writing to giving you formal notice of the termination of my service with you one month from now. The health of my wife makes...
A.
according
B.
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account
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【单选题】I don't like talking on ____ phone; I prefer writing ____ letters. [ ]
A.
a; the
B.
the; /
C.
the; the
D.
a; /
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