Today we     1     (use) chemicals in almost every part of our lives, hoping to make life faster and more convenient.    2     we are most familiar with may be the chemical we use at home to kill flies and other disease-carrying pests. Farmers also use them in the soil     3     (help) their plants grow fast and become strong. However, the discovery of new ways to use chemicals have brought problems as well as benefits.

Just like spoken language, body language varies from culture to culture. The gesture for “OK” has different     1     (meaning) in different cultures. In Japan, someone who witnesses another person employing the gesture might think it means money. In France, a person encountering an identical gesture may interpret it as meaning zero. However, you should avoid     2    (make) this gesture in Brazil and Germany, as it     3     (consider) impolite.