The correct spelling of the phrase "wast impressive" is actually "was impressive." The use of "wast" is an archaic form of the past tense of "to be" that is not commonly used in modern English. The correct pronunciation using IPA phonetic transcription would be /wɑz ɪmˈprɛsɪv/. It's essential to ensure that you use the correct spelling and pronunciation to avoid confusion and ensure clear communication in both written and spoken language.