Verified answer

At last it was time to shut up the office.

Was is at last time to shut up the office?

What was it time to do?

Was it time to shut up or to open the office?

At last it was time to shut up the office, wasn't it?

What was it?

The Ghost of Cristmas Present changed Sgrooge's home completely 

Did the Ghost of Cristmas Present change Sgrooge's home completely?

What  The Ghost of Cristmas Present change?

Did the Ghost of Cristmas Present change Sgrooge's or Brown's home completely?

The Ghost of Cristmas Present changed Sgrooge's home completely, didn't he?

Who changed Sgrooge's home completely?