You are given a question, its answer, and a sentence that supports the question, i.e., the answer to the question is inferable from the sentence. In this task, you need to paraphrase the given sentence so that the paraphrased sentence still supports the question i.e. you can still infer the answer to the question from the paraphrased sentence. Do not write a paraphrase with a minor change in the given sentence e.g. replacing the word "one" with "a". Instead, try to write a paraphrase that contains new words, i.e. the words that are not present in the input sentence.
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Question: Question: In weather terms, what do you call the boundary between two air masses? 
Answer: front. 
Sentence: In weather terms, the boundary between two air masses is called front.

Answer: A front is the boundary between two air masses in weather terms.


Question: Question: Which of these is an example of liquid water? 
Answer: Rain. 
Sentence: Rain these of is an example of liquid water.

Answer: Rain is a form of liquid water.


Question: Question: If a substance has a ph value greater than 7, what does it indicate? 
Answer: base. 
Sentence: If a substance has a ph value greater than 7,that indicates that it is base.

Answer:
7 ph indicates that it is a base.