In this task, you are given a paragraph, and your task is to construct a question from the given passage. Construct question in such a way that (i) it is well explained in the paragraph, (ii) the words may/may not be present in the paragraph, (iii) it should start with what/how/describe. Avoid creating a question that (i) is just relevant to one or two sentences, and (ii) not relevant to passage. 
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Question: Water comes into contact with something made of iron. The water combines with carbon dioxide in the air to form carbonic acid. As the acid is formed, the iron starts to dissolve. Some of the water breaks down into hydrogen and oxygen. The free oxygen and dissolved iron bond together. They form iron oxide, which is rust. 

Answer: How does rust form?


Question: Acid rain makes waters acidic. Causes them to absorb aluminum from soil. The water runs off from the soil into lakes, streams, etc. Fish and their eggs die. Frogs and plants die. Insects and other wildlife die. The ecosystem is out of balance, causing further problems. 

Answer: Describe how acid rain can affect the environment.


Question: Choose what you want to write your letter on. Think of what you want to say. Write some nice things!. Place the letter into an envelope. Put a stamp on the top right corner of the face of the envelope. Write the address of the recipient on the envelope. Put the envelope in your mailbox. Raise the flag on your mailbox, indicating to the mailman that you have outgoing mail. 

Answer:
Describe the process of writing and posting a letter