399. Companies could also reduce prices for those who stayed to eat food on their premises, offer money-off vouchers (中巴金券) or other incentives for those who returned packaging and put more bins at strategic points in local streets, not just outside their premises.
本句的主干是Companies could also reduce..., offer...and put...who stayed to eat food on their premises和who returned packaging均为定语从句，修饰各自前面的those。premises意为“场所，经营场址”。如：
Beverages sold in this restaurant can only be drunk on the premises.
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