A function execution instruction system includes a function execution instruction unit configured to instruct execution of one or more functions, a sentence input unit configured to input a sentence, an execution function determination unit configured to determine a function the execution of which is instructed on the basis of an input sentence, a time information extraction unit configured to extract time information indicating a time from the input sentence, and a time specification unit configured to, in accordance with a determined function, specify a time used for the execution of the function on the basis of extracted time information wherein the function execution instruction unit instructs the execution of the determined function, which uses a specified time.