二次雷达天线存在两个波束，控制波束应当（）。

Amendments to the initial clearance will be issued at anytime an air traffic controller deems such action necessary to （ ） .

In AFTN telegraph, the priority indicator for urgent messages is （ ）.

Flight level 12000ft equals to （ ） .

“I want to divert to shanghai” is equal to （ ） .

When an aircraft is being subjected to unlawful interference, the pilot should try to notify （ ） of this fact.

When pilot say “Did you pick it up on your screen?”, that means （ ） .

If a IFR flight is “cleared as filed”, that means （ ） .

ATC clearance does not contain （ ） .

When pilot sets an altimeter setting to a QNH, that will indicate （ ） .

When pilots set a pressure of 29.92 in mercury to indicate （ ） .