The suffix -able forms adjectives that mean:
1 able to be: calculable.
2 due to be: payable.
3 subject to: taxable.
4 relevant to or in accordance with: fashionable.
5 having the quality to: suitable | comfortable.
"-ward" isn't any part of speech. It's a suffix.
The suffix for speech is "-ology", such as in the term "speechology" which refers to the study or science of speech.
When you add the suffix -ous to the word "poison," it becomes an adjective - "poisonous."
The suffix -itis forms a noun, indicating inflammation or a medical condition.
The noun 'hesitation' becomes a verb by removing the suffix -ion: hesitate.
A word with the -able suffix is usually an adjective.
The suffix affects a word's part of speech. For example, the word 'happy' is an adjective. When you change the suffix, it changes the part of speech. If you change 'happy' into 'happiness' it becomes a noun; when you change it into 'happily' it becomes an adverb.
It's a suffix.
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The word "-ing" is a suffix. You will see this suffix on the end of gerunds.
A suffix changes a word's part of speech. For example, the word 'happy' is an adjective. But when you add a suffix, which is an ending, it can change the part of speech. Happily is an adverb. Happiness is a noun.
"-ward" isn't any part of speech. It's a suffix.
Suffixes cannot be parts of speech. Now the suffix emia is usually associated with words that are nounds take : leukemia : for example
determines its part of speech.
noun
"-ical" isn't any part of speech. It's a suffix (noun) added to a word to create an adjective.
Adding or subtracting a suffix often changes a word's part of speech.