You shouldn't disrupt other people.
Larry is in the library when someone calls him on his cell phone.
Larry wants to answer the phone.
Larry whispers as he answers the phone and continues the conversation outside.
Larry answers the phone and continues to talk while the people in the library are reading.
Larry is able to carry on his conversation while the people in the library read their books.
The people in the library are annoyed and start to shush at Larry.