Some hospitals have doctors that take on different duties such as monitoring the wards, to act as a guardian sounding a warning at the first sign of a patient in danger, and receiving new patients who require hospitalization.
A to act as a guardian sounding
B to act as guardians and to sound
C to act as guardians and sound
D acting as guardians and to sound
E acting as guardians and sounding
E for parallel structure
monitoring.. acting.. sounding...receiving..
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