– If you can’t cut the mustard, I’ll find someone else to finish the job.
– I had high expectations for him, but he just couldn’t cut the mustard.
– This toaster can’t cut the mustard anymore. No matter what setting you choose, your toast comes out charred!
– That guy looks like he’s 110 years old—I’m sure he can’t cut the mustard stocking shelves all day!
– I need a bigger knife for these large fruits; this one doesn’t cut the mustard.
– If he can’t cut it, then we’ll get someone else to do the job.
 

 
» Vocabulário:
 
anymore – mais
but – mas
charred – carbonizado (a)
expectations – expectativas
if – se
guy – cara
high – alta
him – ele
knife – faca
large – grande
no matter – não importa
job – trabalho, serviço
just – “simplesmente”
setting  – configuração
shelves – prateleiras
someone – alguém
sure – certeza
that – aquele (a)
these – estes (as)
this – este (a)
to choose – escolher
to come out – sair
to do – fazer
to find – encontrar
to finish – terminar
to get – conseguir
to look like – parecer
to need – precisar
to stock – abastecer, repor
toast  – torrada
toaster – torradeira
 
Como perceberam em algumas frases, podemos até substituir o CAN’T por COULDN’T, para podermos passar a ideia de “conseguir” (dar conta) no presente e no passado, respectivamente.
 
Obs.: Outra maneira de dizer essa expressão é “can’t cut it”.

 
See you!