The first 2 columns show whether the word takes or when it is weak. If it takes final this should be regarded as the 'happY' vowel, i.e. it may become , especially if it is followed by a vowel in the next word - look in column 4.
Column 3 shows forms which lose their initial h except at the beginnings of utterances
Columns 4-8 show words which change before vowels, and the changes concerned. An arrow means "becomes".
Column 6 applies only to non-rhotic accents; the rhotic accents will always have a final -r in these words. Also, many American accents do not change to as in column 5.
Columns 7 and 8 only concern the words the and a (an). The change in the before vowels does not take place in many American accents.
Finally, column 9 shows those words which retain their STRONG vowel at the end of utterances, BUT REMAIN UNSTRESSED.
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