In the text,

the modal disjunct “probably” (l.13) expresses the author’s view on how likely it is that what follows this word is true.

In the text,

the word “its”, in “of its kind” (l.20), is the full form of it’s.

In the text,

the noun “Circle” (l.1) functions as an adjective.

In the text,

the relative pronoun “that” (l.1) can be correctly replaced by which.

In the text,

the article “a”, in “a circle” (l.2), can be correctly replaced by the.

In the text,

the function word “as” (l.10) can be correctly replaced by like.

In the text,

the phrase “They can be used as warmers” (l.12) is the passive voice of You can use them as warmers.

In the text,

the word “filler” (l.13) is a noun formed from the verb to fill.

In the text,

the phrase “at the end” (l.13) is synonymous with in the end.

In the text,

the use of “will”, in “each student will have” (l.32), shows agreement.