Jane is one of the best students in her class who _____by their teacher.
A. are praised
B. is praised
C. praised
D. praising
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The whole class _____the teacher attentively.
A. are listening to
B. is listening to
C. are listening
D. has listened
This is an illness that can result in total blindness if _____untreated.
A. left
B. being left
C. is left
D. it left
A reagent is any chemical that reacts in a predictable way _______withother chemicals.
A. when mixed
B. when is mixed
C. it mixed
D. when mixing
As a general rule, snakes don't bite unless ________.
A. are offended
B. they offended
C. offending
D. offended
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