>Thank you very much. What would be the difference in pronunciation between "connais" and "connai"?
>

It's like the difference in pronounciation between the futur tense and the conditional tense

Je partirai (I will leave)
Je partirais (I would leave)

That said, "je sais" is pronounced both ways

The advantage of Spanish is that when you see a word you know how to pronounce it, whereas in other languages you do not

The c in une seconde is pronounced as a g in go