I'd like to know in which situations can we use already in a question. This question appeared in my English book "What wildlife has she seen already?"I've always been taught that we use yet in questions and already in affirmative sentences. Another point is: isn't already supposed to be in the middle of the sentence???I'm so confused...
'Already' commonly appears in questions such as the one you have given.

Not a rule, but a guideline: 'already' commonly appears in affirmative sentences (questions and statements), and 'yet' commonly appears in negative sentences (questions and statements). This is not absolute, though.
Veteran Member114,970
SystemAdministrator: A system administrator takes care of the inner workings of the entire system. These users have the ability to promote, ban and modify other users.Teachers: Users in this role are certified teachers. This may include DELTA, CELTA, TESOL, TEFL qualified professionals. Email a scan of your qualification to an admin, if you wish to be considered.