Complex sentence: Both rely on speech act theory developed by Searle in 1960 and enhanced by Winograd and Flores in the 70s and define a set of performatives and their meaning (e.g. ask-one).
Split into simpler sentences: Both rely on speech act theory developed by Searle in 1960 and enhanced by Winograd and Flores in the 1970s. They define a set of performatives and their meaning (e.g. ask-one).