question: On what grounds did Apple sue Microsoft and Hewlett-Packard in 1988 ?
answer: they infringed Apple 's copyrighted GUI
turker_answer: Apple sued Microsoft and Hewlett-Packard in 1988 on that grounds that they infringed on Apple 's copyrighted GUI .
rule-based: Did Apple sue Microsoft and Hewlett-Packard in 1988 on they infringed Apple 's copyrighted GUI .