instruction:
In this task, you are given a word, followed by a sentence. You should respond with a valid sentence which contains the word with the same meaning as in the given sentence. For example, if the given sentence refers to a 'fly' as the insect, you should not respond with a sentence which uses 'fly' as the verb. You may use the word in a different tense than is given. For example, you may use the word 'ended' in the output where the given input word is 'end'.
question:
night 
 Sentence: From noon till night.
answer:
They worked from morning to night.


question:
mystery 
 Sentence: How it got out is a mystery.
answer:
The truth behind the events remains a mystery.


question:
key 
 Sentence: The key to solving this problem is persistence.
answer:

The key to development is economic integration.