ohne … zu, statt … zu (and ohne dass, statt dass)

INTRODUCTION

'He left without saying goodbye', 'He's playing instead of studying' — structures that English builds with 'without -ing' and 'instead of -ing' are built in German with 'ohne … zu' and '(an)statt … zu'. As you know 'um … zu', the rules will feel familiar: if the subjects are the same, a zu-Infinitiv; if they are different, a dass clause.