tro choi do vui

I'm has full keys but I can't open any door. What I am ?

• keys

• piano

• lock

• keyboard

I am what I am, but if you know what I am, I'm not longer what I am.

• I am

• computer

• Brian

• secret

what always coming but never arrives ? 

• today

• yesterday

• tomorrow 

• the past

what has face and two hands but don't have any arm or leg ?

• a spider

• a clock

• a tree

• a bear

what belongs to you but yet it use more by other than your self ?

• the name

• clothes

• phone

• phone number

what has to be broken before you can use it ?

• a class

• a seal

• a window

• an egg

name