[Grammar] sometimes in present perfect.

[naemeria]

HI!!I came across those two sentences in a test in this site..
1)Never have I seen such a mess
2)Sometimes I have seen such a mess.
My questions are:
a)I understand that the first is correct (inversion-wise) but shouldn't there be a ''never before'' instead of just ''never''?
b)Can ''sometimes'' be used in present perfect?I'm not sure about it but it seems totally inappropriate used that way here.Looking forward to an answer.

 

[5jj]

1)Never have I seen such a mess
2)Sometimes I have seen such a mess.
My questions are:
a)I understand that the first is correct (inversion-wise) but shouldn't there be a ''never before'' instead of just ''never''? No - it's fine as it is.
b)Can ''sometimes'' be used in present perfect?

We would normally expect to see 'sometime' between 'have' and 'seen', but it can go at the beginning and end of the clause. It means something like 'on various occasions in a period of time extending up to the present'. The present perfect is fine here.