Question

Group I. If the root is a full word , the ending is usually -able.

Group II. When the root is a full word except for a final e , the forms usually are spelled with -able.
Group III. The suffix -able always follows i .
Group IV. When the root has other forms built on the letter a , the -able form is used.
Group V. When the root ends in hardc or g, -able is used.
Group VI. When the root is not a full word, -ible is used.
Group VII. When the word has an immediate -tion form, -ible is used.
Group VIII. When the root ends in ns , miss , or soft c or g , - ible is used.
What ending should this word have? What mnemonic group applies most closely to it?

exhaust___

Group:___

Answer 1

The answer: " -ible"

The word is: "exhaustible" .

Group: VII .
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The following rule applies, as mentioned within the question, and as quotated DIRECTLY from THIS VERY QUESTION:

"Group VII. When the word has an immediate -tion form, -ible is used."
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Note: The word, "exhaust" ; does, in fact have an "immediate -tion form" ;

since the word, "exhaust" ; ends with the letter, "t" ; and since the word, "exhaust" ; has an "immediate -tion" form, which is the word, "exhaustion" ; then "Group VII" applies.
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The word is "exhaustible" ; (note that the ending is: "-ible").

Group: VII .
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