---Why couldn’t they meet us at five o’clock?---Because they were delayed by ________.
A. heavy traffic
B. heavy traffics
C. crowded traffic
D. crowded traffics
---May I take your order now?---We’d like three black ________ and two green _______.
A. coffee; cups of teas
B. coffees; teas
C. cups of coffee; tea
D. cup of coffees; teas
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