For users, microkernel technology promise { A }, compact, and sophisticated operating systems that are typically { B }across a range of hardware platforms. These operating systems will be customizable to let users run multiple operatin system and application "per-Sonalities" on top of a single microkernel { C } .Microkernel-based systems can provide this flexbility because the core operating.

　　System functionc are { D } from the large number of utilities, features and extension that are layered on top of them. As a result, updation and maintaining operating system is easier, since developers don't have to modify the { E } every time they must add a new feature.

　　供选择的答案：

　　A：①slow ②fast ③quickly ④speed

　　B：①moveable ②made ③portable ④use

　　C：①bases ②foundations ③systems ④foundation

　　D：①separate ②connected ③compared ④selected

　　E：①core ②center ③heat ④utility

　　【解析】

　　参考译文：对用户来说，微内核技术有希望实现能在许多硬件平台上移植的快速、紧凑和先进的操作系统。这些操作系统可以定制化，以使用户可在单个微内核基础上运行多个操作系统和应用程序。

　　基于微内核的系统之所以能够提供此灵活性是因为核心的操作系统功能与大量用程序、特征和扩展功能是分离的。它们分层加于核心功能上，其结果是使更新和维护操作系统更加容易了。因为开发人员不必在每次加入一个新特色时都修改核心。

　　【答案】A：② B：③ C：④ D：① E：①