adverb
BAD : As usually, he arrived five minutes late.
GOOD : As usual, he arrived five minutes late.
BAD : The food wasn't the same as usually.
GOOD : The food wasn't the same as usual.
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as usual (NOT as usually ): 'John's late as usual.' 'As usual, everyone was out in the garden when I arrived.'
the same as usual (NOT ... as usually ): 'Apart from his hair, he looked the same as usual.'