根据英文解释写出相应的英文词汇~急
1、a highly structured high-level programming language developed by Niklaus Wirth of ETH,a university in Zurich,Switzerland
2、a symbol which indicates the action to be performed on operands
3、a description,reference or explanation added to or interspersed among the statements of the source language,which has no effect in the target language
不是翻译,而是要英文的答案哦,是和计算机相关的