"It sounds like you are asking what parts of speech may be a subject of a sentence. Generally, one would tell you that nouns or pronouns can be subjects of a sentence. But sometimes a word that looks like a verb could also be the subject of a sentence."

See examples at web source:
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"It sounds like you are asking what parts of speech may be a subject of a sentence. Generally, one would tell you that nouns or pronouns can be subjects of a sentence. But sometimes a word that looks like a verb could also be the subject of a sentence."

See examples at web source:
http://en.allexperts.com/q/Lan...

Also see:

"The Parts of the Sentence" at this web source:
http://www.arts.uottawa.ca/wri...