【单选题】_____ keep the insects out, she shut the window. [ ]
【单选题】In the streets,____________ was a hard job for the traffic police to keep the traffic in order. [ ]
【判断题】金属结晶后的晶粒越小,晶界数量越多,则性能越差。
【单选题】In order to keep the line moving, customers with lengthy ________ are required to do their banking inside.
【判断题】金属结晶后的晶粒越小,晶界数量越多,则性能越好。
【单选题】How do librarians keep books in order?
A.
They arrange the books in alphabetical order.
B.
They put the books into a card catalogue.
C.
They give a number to each book.
D.
They put the books on the shelves.
【简答题】Users need to wipe ______ from the LED in order to keep it working well.