Can someone pls tell me when to use 'a' and when to use 'ab'? I'd be very thankful!
A before a consonant; ab before a vowel (or an h, if I am not wrong).
They follow rules similar to a/an in English. 'a' is used when the following word begins with a consonant and 'ab' is used when the following word begins with a vowel or h.
False positive: Pueri ab Italiam veriunt.
They can't do anything about false positive, only the Duo sofware programmers can.
That is just true negative, aka typo(s).
Interestingly, 'Pueri ex Italia veniunt' is not accepted.
If you google 'Italia veniunt' the 'ex Italia' hits outnumber 'ab Italia' by far.
'ex italia' is more like you visited italy . 'ab Italia' means you're italian(like in that sense 'i come from italy')
Thanks, that makes a lot of sense.