3. A method for providing executable machine commands to a computer system in accordance with natural language inputs in a predefined natural language subset which has a predefined correspondence to a set of executable machine commands, received from an unskilled user, comprising the steps of: presenting to the user the set of permissible next inputs, which can provide a next word in a permissible natural-language input; repeatedly, as soon as the user designates one of the permissible next inputs presented, cumulatively parsing all words in a current sequence which have been entered by said user, and displaying to said user the set of all possible next words which could form a continuation of a legal input, in accordance with said predefined natural language subset, whereby said unskilled user's choices are constrained to include selection of only legal successive sentence elements, until said user has entered a completed sentence; and then translating said completed sentence into executable machine commands, in accordance with said correspondence therebetween.
3. A method for providing executable machine commands to a computer system in accordance with natural language inputs in a predefined natural language subset which has a predefined correspondence to a set of executable machine commands, received from an unskilled user, comprising the steps of: presenting to the user the set of permissible next inputs, which can provide a next word in a permissible natural-language input; repeatedly, as soon as the user designates one of the permissible next inputs presented, cumulatively parsing all words in a current sequence which have been entered by said user, and displaying to said user the set of all possible next words which could form a continuation of a legal input, in accordance with said predefined natural language subset, whereby said unskilled user's choices are constrained to include selection of only legal successive sentence elements, until said user has entered a completed sentence; and then translating said completed sentence into executable machine commands, in accordance with said correspondence therebetween. 4. The method of claim 3, wherein said predefined natural language subset is defined as a context-free grammar and a lexicon.