On the island of New Zealand there is a grasshopper-like species of insect that is found nowhere else on earth. New Zealanders have given it the nickname weta which is a native Maori word meaning “god of bad looks”. It’s easy to see why anyone would call this insect a bad-looking bug. Most people feel disgusted at the sight of these bulky(笨重的)，slow-moving creatures.

Wetas are natural creatures; they come out of their caves and holes only after dark. A giant weta can grow to over three inches long and weigh as much as 1.5 ounces. Giant wetas can hop up to two feet at a time. Some of them live in trees and others live in caves. They are very long-lived for insects and some adult wetas can live as long as two years. Just like their cousins grasshoppers and crickets wetas are able to “sing” by rubbing their leg parts together or against their lower bodies.

Most people probably don’t feel sympathy for these endangered creatures but they do need protecting. The slow and clumsy wetas have been around on the island since the times of the dinosaurs and have evolved and survived in an environment where they had no enemies until rats came to the island with European immigrants. Since rats love to hunt and eat wetas the rat population on the island has grown into a real problem for many of the native species that are unaccustomed to its presence and poses a serious threat to the native weta population.

A food additive (添加剂) is any substance that is added to food. Many people are put off by the idea of “chemicals in food.” The truth is that all food is made up of chemicals. Natural substances like milk, as well as man-made ones like drinks on sale in the market, can be described by chemical formulas. Some chemical substances are indeed harmful, but a person who refused to consume any chemicals would find nothing to eat.

The things we eat can be divided into natural and man-made substances. Some people feel that only natural foods are healthy and that all man-made ingredients are to be avoided. But many natural chemicals, found in plants and animals, are harmful when eaten, and some laboratory-made substances increase the nutritional value of food. Other chemicals have natural and man-made forms that are exactly alike: vitamin C is vitamin C, whether it comes from a test tube or from an orange. Like “chemical”, “man-made” doesn’t necessarily mean “not fit to eat”.

Food additives are used for many reasons. We add sugar and salt and other things to foods we prepare at home to make them taste better. Food producers have developed a range of additives that stabilize（使稳定）, thicken, harden, keep wet, keep firm, or improve the appearance of their products. Additives can make food more convenient or nutritious, give it a longer shelf life, and make it more attractive to the consumer, thus increasing the sales and profits of the producers.

Food additives are presently the centre of a storm of serious argument. Food producers have been known to use additives that have not been proved safe; some substances in common use have been proved unsafe and have been taken off the market. Many people feel there’s a risk of eating food to which anything has been added. But food additives are now regulated by the FDA of the federal government, and new additives will go through strict testing before they can be placed on the market. For most people, the chances of developing serious side effects (副作用) from the long-term use of presently approved (批准) food additives are very small.

Confidence is very important in daily life. It can help you to develop a healthy attitude. A study shows that the people who are more confident are much happier.    11    . But how to be more confident? Here are some suggestions:

● Speak loud   When you are not confident, you can’t do well what you want to do. You speak in a voice so low that other people can hardly hear you. Try to speak loud enough so that people can hear you clearly.     12    

● Play sports   Physical exercise makes you tired but completely relaxed. A strong body helps you be full of confidence.

● Encourage yourself   Write down a list of things you did during the day to see how many things you have done well. Did you finish your homework? Did you tell a joke that made everybody laugh?     13    

●     14     Fear comes along with failure. But it’s easy to overcome (克服) if you know that failure is part of your life. Don’t hide your head just because you said something stupid last time. Try to start again and believe you can do better.

● Pick up a hobby   If you like singing, sing as much as you can.     15     And it will make you happy and confident.