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general::
Phrase(s): base something (up)on someone or something
to ground something, such as one’s opinion, decision, or thinking, on someone or something; to found one’s ideas or attitude on something. (Upon is more formal and less commonly used than on.) • I base my opinion on many, many facts. • I based my opinion upon my own seasoned judgment.
McGrawhill's American Idioms And Phrasal Verbs