she hasn't won an a tennis championship for two years.
Does this sentence mean she won a championship two years ago or she didn't win a championship two years ago?
she hasn't won an a tennis championship for two years.
Does this sentence mean she won a championship two years ago or she didn't win a championship two years ago?
Correcting your sentence:
She hasn't won a tennis championship for two years.
Alternately:
She hasn't won a tennis championship in two years.
Those mean that either: