If you want to raise, you say 'I raise' and give a value. The value includes the original bet and your raise. So if someone bets $5, and you want to raise it by $10, you would say 'I raise, $15'. This makes your total bet $15, and he has to put in $10 to call.

If you want to call ('I see your X'), then you just say 'I call'. If you say on the table 'I see your X and raise you Y', you're calling by saying 'I see your X', which means you can do no further betting. Ergo the second part of your phrase is a string bet, which isn't allowed.

The same goes for your physical motions. You have to put your chips in all at once, you can't drag a stack at a time into the pot. If you push one stack into the pot and reach for another stack after letting go, you can't add any more chips. You've either called or raised, based on how much you put in (bare minimum is a call, if you're short you have to add more chips).

The dealer will usually warn you and may even be very kind the first time and let you correct your mistake, but you're lucky to ever have that happen.