I think it means "Long Time No See"
For a long time.
time long past
Long Time No See
It is a long silence or, silent for a long time.
It is asking for the length. It could be a linear dimension (usually the largest) or it could be the duration of time.
A long period of time can mean a great many things. It could mean that something isn't ready or prepared.
What do you mean the time? If you mean the flipping time for one page, then you can set the time by yourself. Normally 0.6 second is recommended. But if you mean how long we read a page of a flip book, that depends on different people.
no sitting there and not moving for a long time
Chronic
no sitting there and not moving for a long time
a long time ago