In this task you are given a sentence. You must judge whether subject of the main clause is singular or plural. Label the instances as "Singular" or "Plural" based on your judgment.

The email, as it was open and apparently unfinished, could have easily been a clue as to the whereabouts of General White and his family.
Singular

One agent, looking at the incoming stream of text messages, says, " They found a cell phone jammer and disabled it.
Singular

Maris crossed her arms.

Plural