颂赞
参考答案：
用以歌功颂德和表彰赞扬的文辞。
观赏花木的芽型因性质不同分为哪几类？
As an operating system repeatedly allocates and frees storage space, many physically separated unused areas appear．This phenomenon is called （ ） .
A．fragmentation
B．compaction
C．swapping
D．paging
