II. Change-of-state le 了used in sentences with different predicates
The new situation marker le了 is used at the end of a sentence in which the predicate is a noun, a stative verb or an action verb. An action verb may be preceded by an optative or modal verb. The change-of-state le了 is also used in shì是and yǒu有sentences.
A. Le了 at the end of a sentence with a noun as the predicate.
A 1.1 Jīntiān xīngqīwǔ
Today is Friday (already). /It has turned into Friday today.
The underlying statement is that time has passed and it has changed from Thursday into a new day, Friday. If le了 is eliminated, the sentence simply announces the day of the week. Compare it with the following sentence which does not have the change-of-state le了.
A 1.2 Jīntiān xīngqīwǔ.
Today is Friday.
This sentence simply states the fact that ‘today’ is Friday.
A. 2.1 Xiànzài yǐjīng shí yuè le.
It is already October now. /It has already become October now.
This sentence shows that time has passed and that it has progressed into a new month, October. Compare it with the following sentence which does not have the change-of-state le了.
A 2.2 Xiànzài shì shí yuè.
It is October.
This sentence simply announces the fact that the month in question is October.