题目内容：
根据下列题干，回答题：There are many kinds of Computer languages. A typical imperative language contains an （ 1 ）_ sub language which approximates the mathematical abstractions of" timeless" functions applied to "space- less" values, where the actual operation sequences and use Of storage space during expression evaluation are organized behind the （ 2 ）. In this setting, values are data structures of low volume, typically a few computer words or less, which means that an illusion of （ 3 ） can be realized by having intermediate re- suits during expression evalution stored at the discretion of the language implementation, and effecting pa- rameter （ 4 ）and（ 5 ）operations through value copying.
请选择（ 1 ）处最佳答案
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