The kitchen is ____ catering for several hundred people.
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They need to ____ some sleccp becasue they stayed up all night talking.
If one person in the group hasn't preapred, it will _____ the whole project.
C. Match the words to make collocations. Then complete the sentences.
主对角行列式和三角行列式的值都等于主对角线上元素的乘积。
A. 对
B. 错
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