Be always doing something

Be always doing something is an English verb form. It uses the progressive aspect, with the adverb of frequency "always". It's used to express frustration or annoyance at a repeated action.

e.g. "my boss is always shouting at me."

"Always" cannot be replaced with other adverbs of frequency - this is a special usage.

Using a copular verb in the progressive sounds a bit weird; e.g. ^?"you're always being late" - and it's probably better use a dynamic verb, e.g. "you're always coming late".