The teacher asked the two students todiscuss the question in a low voice______ they should bother the others

Thank you for the delicious dinner. –______

To keep healthy, Professor Johnson _____ cycling as a regular form of exercise after he retired.[ ]

Nobody but doctors, nurses or those ______ by Dr Hu ______ to enter the patient’s room[ ]

The careless boy lost his key, _______ he had to wait for his mom in the cold.