Finally. = At last or the decisive moment.
I hope that my children will finally get married.
To astound. = Very, very surprised.
I was astounded when my son told me his future plans.
In safe hands. = To be well protected.
Since this building has a number of security systems, I feel that I'm in safe hands.
In the cards. = In the future, something that is going to happen.
One of my sons will marry soon. It's in the cards that I'll have a grandchild soon.
Gotta go. = I must leave or I have to go to the rest room.
I must be at work soon. I can't stay and talk. I gotta go.
F.Y.I. For your information. = To inform someone about something politely.
F.Y.I. your zipper is down.
Zero dark thirty (0 dark30). = Slang for very early in the morning.
I always begin my day at 0 dark30.
It's your call. = It's your decision.
We can go out or stay home. It's your call.
Things are looking up. = Things are getting better.
Things are looking up, so don't look down.
To sign off on something. = To give the O.K. for something.
Before we upload these videos, the chief has to sign off on them.