About nothing but language. Not the film itself.

1. say what you mean or mean what you say?
I finished reading Alice's Adventures in Wonderland yesterday. And some lines in The Last Emperor are remniscent of those in Alice.

From Alice:
`Then you should say what you mean,' the March Hare went on.
`I do,' Alice hastily replied; `at least--at least I mean what I say--that's the same thing, you know.'

From Emperor:
Mr. Johnston, "If you cannot say what you mean, My Majesty, you will never mean what you say. "

These two expressions are a matter of words. In the former example, it highlights the language game of shifting word orders and the differences between the expressions. It alters the meanings by changing the presumptive conditions. Whereas the latter one puts the emphasis on the conditional relation between the two actions.

2. almost all lines are in English.
the comrades in Emperor speak English locally, especially those directors in the prison, though I feel a little bit uncomfortable to hear English spoken in the forbidden city in the beginning of the film.