In which sentence does a noun clause function as the subject?

Before the math competition, be sure to memorize whatever formulas you will need.

We practice after school in whichever rooms have the most board space for our work.

Bring extra calculators for whoever forgets to bring theirs along.

Whoever understands how to multiply and divide numbers by 10 can easily use the metric system.

Question

In which sentence does a noun clause function as the subject?

Before the math competition, be sure to memorize whatever formulas you will need.

We practice after school in whichever rooms have the most board space for our work.

Bring extra calculators for whoever forgets to bring theirs along.

Whoever understands how to multiply and divide numbers by 10 can easily use the metric system.

ItzAgar · Answer

Okay so what's the definition of clause?