There is one sentence in the choices below that does NOT have a grammar error by shifting mood or verb voice incorrectly. Which sentence is it? (Illuminate) (1 point)
• When the operator turned on the machine, a squeaking sound was heard.
• Read the first two chapters, and then you should meet with the study group.
© All members should register for the trip by noon Friday, and don't be late.
O Two children left the classroom without permission, but they were found immediately.