1. Our director of product development is responsible fo _________ innovative ideas for new types of light bulbs.
2. Guests can pay for their hotel rooms and other inciental charges with _______ cash or credit card when they check-out.
3. Your passport will be _____ safe inside one of our hotel's security boxes.
출처 : e4u 토익 [김태균의 실전 5분 토익 中 ]