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At one meal, the first main course is often ______.
A. meat, fish and poultry
B. either meat or fish
C. meat, fish and poultry but no seafood
D. none of the meat, fish and poultry
下列各项中，不属于进程特征的是( )。
A. 静态性
B. 并发性
C. 异步性
D. 独立性
A group of soldiers marched forward, guns ______ in hand.
A. hold
B. held
C. holding
D. to be held
Today, the Australian population is still mainly of British ______.
A. descent
B. descend
C. decadence
D. descendant
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