Find all files in the current directory (denoted by ~/*) that are of type file (denoted by -type f) and are larger than 20 megabytes (denoted by -size +20M) and execute the command "cp {} /tmp/large-files/" on each of them (denoted by -exec cp {} /tmp/large-files/ \;).
find ~/* -type f -size +20M -exec cp {} /tmp/large-files/ \;