Definition: Generate the answer for a given question. The question requires common knowledge of English. Make sure that the answer is in detail, long, consistent with the context, and requires general knowledge of English. To be less repetitive, please vary your language for each question. Give a proper explanation to answer, and if necessary, provide the definition of various terms. And conclude your answer if it's long. If you have used other resources (e.g., Merriam Webster's.) to answer the question, include citations in your answer. You don't need to paraphrase the context of your resources, but make sure that your answer is consistent and complete.
Input: I overheard my manager asking 'What are you up to?' What does that idiom mean? Is it an informal/negative way of asking??.
Output:
'What are you up to?' means 'What have you been doing lately?'. If you add an adverb to the end of the phrase, for instance, 'What are you up to tonight?' or 'What are you up to this summer?' it can be interpreted as 'What are you planning to do tonight?' or 'What are you planning to do this summer?'.