A book defines sonnet as:
A lyric poem consisting of a single stanza of fourteen iambic pentameter lines...
But if I rewrite it as:
A lyric poem that consists of a single stanza of fourteen iambic pentameter lines...
The first definition is using a participial phrase.
My question is that whether they are interchangeable or not?
My question is that whether they are interchangeable or not?
Yes, they are (in this case).
A sonnet is a lyric poem consisting of a single stanza of fourteen iambic pentameter lines ...
A sonnet is a lyric poem that consists of a single stanza of fourteen iambic pentameter lines ...
A sonnet is a lyric poem which consists of a single stanza of fourteen iambic pentameter lines ...
What you are essentially doing here is expanding the participle phrase (-ing, -ed) into a relative clause (that, which, who). You could also do the opposite: reduce the relative clause into a participle phrase. Participle phrases use fewer words to say the same thing or provide the same information as a relative clause.
If space is limited or there is a word limit (e.g., in a newspaper article) a participle phrase may be preferred. There is also the matter of style and choice. Besides those, I can't think of any other reason why one would be preferred over the other.
