Im Indian and this makes no sense sorry :(
This sentence would probably be a citation in APA style. Citations on research papers are very important since they give due credit to the original owner of the statement. Statements that don't have citations tells the readers that those statements are of the researcher/s alone which would be a problem for them if found out that it wasn't theirs to begin with. This would result to a work of plagiarism which is a grave sin in constructing research papers and is more equated with the act of stealing.
<span>Juliet is surprised at Romeo's presence because she did not know that he was there.
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Hello!
Here, the tense used is the past imperfect tense.
Hence, the correctly written sentence will be :
