The Head-Driven Phrase Structure Grammar (HPSG) is a grammar theory developed by Pollard and Sag (1985). It uses a uniform formalism and is organized in a modular way which makes it attractive for Natural language processing.
... for Greece; with an order for 24 units from Austria pending.
In British service, the aircraft is supposed to replace the Tornado F3 and the Jaguar GR3A[?].
The ...