Advertisements are a good __________ sell products or services.

I wished to make a round-the-world tour by plane but I hadn't enough money to pay for the ___.

I keep medicines on the top shelf, out of the children’s________.

 Mary was given a huge pay rise as a       for her great efforts in improving sales.

—Do I need to give a tip if I eat at a fast food restaurant in the United States?—Yes , it’s a common       to tip waiters in a restaurant.