International English for minimum intelligibility (in Gimson’s Pronunciation of English by A Cruttenden)

Consonants

1. All voicing distinction must be kept: /s/ vs /z/: Sue & zoo, /v/ vs /f/: v & fee, etc
2. /r/ vs /l/: road & load
3. /v/ vs /w/: vet & wet

Vowels

1. A distinction is to be maintained only by 5 pairs of short & long vowels. Therefore, a quality distinction in these pairs has to be maintained – seat & set & sat, port & part but not in these – feet & fit, look & Luke, port & pot.

Connected speech

1. Stress can be placed, habitually, on the first syllable (trochee) but no attempt need to be made to weaken syllables.
2. No effort need to be made to learn intonation patterns.