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Professor Fizzle is documenting his latest (and slightly explosive) experiment. Help him record the results by selecting ALL the grammatically correct observations.
The correct answers are Both of my eyebrows were singed off by the blast, Half the laboratory is covered in green slime, and All of the bubbling potions evaporated instantly.
With the quantifiers all, both, and half, the word "of" is optional when followed by a noun phrase with a determiner (e.g., Half the laboratory OR Half of the laboratory).
However, there are two strict rules:
- If you use a pronoun, you must include "of" (e.g., All of them, NOT All them).
- If you use "of" before a noun, you must include a determiner like "the" or "my" (e.g., Half of the laboratory, NOT Half of laboratory).