Final answer:
The word that will make the sentence grammatically correct is 'is' because the subject is singular.
Step-by-step explanation:
The correct word that will make the sentence grammatically correct is is.
The subject of the sentence is 'Pulling weeds from the garden', which is a singular noun phrase. Therefore, the verb should agree with the singular subject, so 'is' is the correct choice.
For example, the correct sentence would be: 'Pulling weeds from the garden is one of the things I am supposed to do.'
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