In the following passage there are blanks which have been numbered. For each blank, four words are suggested. Find out the most appropriate word to fill in the blank.

If you ask some people, “How did you learn English so well ?” You may get a surprising answer : “In my sleep!”

These are ......76 who have taken part in one of the ..............77 exeriments to test learn- while-you-sleep methods, .......78 are now being tried out in several countries, and with ..........79 subject, of which English is only one. Specialists say that .........80. sleep study method speeds language learning tremendously.