题型6——Process Diagram（流程图）

Cambridge IELTS 6

TEST 3:

The diagrams below show the life cycle of the silkworm and the stages in the production of silk cloth.

Summarise the information by selecting and reporting the main features, and make comparisons where relevant.

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The first diagram shows that there are four main stages in the life of the silkworm. First of all, eggs are produced by the moth and it takes ten days for each egg to become a silkworm larva that feeds on mulberry leaves. This stage lasts for up to six weeks until the lava produces a cocoon of silk thread around itself. After a period of about three weeks, the adult moths eventually emerge from these cocoons and the life cycle begins again.

The cocoons are the raw material used for the production of silk cloth. Once selected, they are boiled in water and the threads can be separated in the unwinding stage. Each thread is between 300 and 900 meters long, which means they can be twisted together, dyed and then used to produce cloth in the weaving stage.

Overall, the diagrams show that the cocoon stage of the silkworm can be used to produce silk cloth through a very simple process.

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Salmon begin life as eggs on a pebbly riverbed, hidden among reeds in the slow-moving upper reaches of a river. After five to six months the eggs hatch into “fry”. For approximately the next four years, these baby salmon will live in the lower, faster-flowing waters of their river. During this time they measure between three and eight centimetres in length.

By the time salmon reach twelve to fifteen centimetres, they are termed “smolt”, and at this time they migrate further downriver into the open sea. After five years at sea the salmon will have grown to adult size, which is between seventy and seventy-six centimetres. They then begin swimming back to their birthplace, where they will lay their eggs, and the cycle starts anew.   

In summary, the salmon passes through three distinct physical stages as it grows to maturity. Each of these stages takes place in a very different aquatic location. It is noteworthy that the first two stages of this fish‟s life occur in a freshwater environment, while the third stage is lived in saltwater.