شرکت در آزمون آنلاین زبان انگلیسی 1 - زبان انگلیسی 1 | آزمون شماره 13024

A: May I speak to Jim? B: Yes, just a moment. I …… him.

The blood is a vitally important fluid for the body. It is thicker than water, and feels a bit sticky. The temperature of blood in the body is 38° C, which is about one degree higher than body temperature. How much blood you have depends mostly on your size and weight. A man who weighs about 70 kg (about 154 pounds) has about 5 to 6 liters of blood in his body. Blood has three important functions.

First of all, the blood transports oxygen from the lungs to the cells of the body, where it is needed for metabolism. The carbon dioxide produced during metabolism is carried back to the lungs by the blood, where it is then exhaled. Blood also provides the cells with nutrients, transports hormones and removes waste products, which the liver, the kidneys or the intestine, for example, then get rid of.

The second one is that the blood helps to keep certain values of the body in balance. For instance, it makes sure that the right body temperature is maintained. This is done both through blood plasma, which can absorb or give off heat, as well as through the speed at which the blood is flowing.

At last, if a blood vessel is damaged, certain parts of the blood come together very quickly and make sure that it stops bleeding. This is how the body is protected against losing blood. White blood cells and other messenger substances also play an important role in the immune system.

What does the passage mainly discuss?

The lion is the most … animal in the jungle.

John was my best and kindest friend. It is so hard to ‎… ‎him, and I do not know what I will do without him.