1. I'm running late.
2. I'm becoming late.
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Does #1 mean #2?
1 is the better expression
RAMAKRISHNAN is right. #1 is better.
In this context, both sentences convey a similar meaning, but there is a subtle difference between them.
1. "I'm running late." - This sentence indicates that you are currently in the process of being behind schedule. It suggests that you are already late or about to be late for something.
2. "I'm becoming late." - This sentence implies that you are gradually transitioning into being tardy. It suggests that you may not be late yet, but you are aware that you will be soon.
While both sentences express the idea of being late, the first sentence is more commonly used and conveys a stronger sense of urgency. It is more straightforward and commonly used in informal situations. The second sentence, while grammatically correct, is less common and might sound a bit odd to native English speakers.