BREAK I hereby indicate the separation between portions of the message. [To be used where there is no clear distinction between the text and other portions of the message.]
BREAK BREAK I hereby indicate separation between messages transmitted to different aircraft in a very busy environment.
CANCEL Annul the previously transmitted clearance.
CHECK Examine a system or procedure. [No answer is normally expected.]
CLEARED Authorised to proceed under the conditions specified.
CONFIRM Have I correctly received the following... ? or Did you correctly receive this message?
CONTACT Establish radio contact with.
ACKNOWLEDGE Let me know that you have received and understood this message
CORRECT That is correct.
CORRECTION An error has been made in this transmission [or message indicated] the correct version is.
DISREGARD Consider that transmission as not sent.
HOW DO YOU What is the readability of my transmission?
READ The readability is:
  1. Unreadable
  2. Readable now and then
  3. Readable but with difficulty
  4. Readable
  5. Perfectly readable
I SAY AGAIN I repeat for clarity or emphasis.
MONITOR Listen out on [frequency].
NEGATIVE "No" or "Permission is not granted" or "That is not correct'.'
OVER My transmission is ended and I expect a response from you. [Not normally used in VHF communication.]
OUT My transmission is ended and I expect no response from you. [Not norma//y used in VHF communication]
READ BACK Repeat all, or the specified part, of this message back to me exactly as received.
RECLEARED A change has been made to your last clearance and this new clearance supersedes your previous clearance or part thereof.
REPORT Pass me the following information.
REQUEST I should like to know or I wish to obtain.
ROGER I have received all of your last transmission. [Under NO circumstances to be used in reply to a question requiring read back or a direct answer in the affirmative or negative.]
SAY AGAIN Repeat all or the following part of your last transmission.
SPEAK SLOWER Reduce your rate of speech.
STANDBY Wait and I will call you.
VERIFY Check and confirm with originator.
WILCO I understand your message and will comply with it.
WORDS TWICE The readability is:
  1. As a request: Communication is difficult. Please send every word or group of words twice.
  2. As information: Since communication is difficult, every word or

group of words in this message will be sent twice.