I figured I would have to dig around for the translation of the script that I was curious about, but suprisingly the third result of my Google search for "saving private ryan knife stab german" provided the answer.

The scene is The death of Private Stanley Mellish (Adam Goldberg) - watch it on YouTube. It's much better in context (with Upham just metres away on the staircase), which I've removed from the below commentary:

As the final battle wages on, Mellish is fighting one-on-one against a German soldier. The German slowly gains the upper hand. Mellish pulls out a knife, but the German is too strong, and pushes Mellish's hand backwards, pointing the blade towards the American's chest. Mellish starts to beg. "Wait a minute. Wait a minute".

The German slowly pushes the knife into Mellish's chest, quietly whispering something in German, which translates as "Give up, you don't stand a chance! Let's end this here; it will be easier for you like this!".

Mellish shakes as his life leaves him and the German leaves the room.

Mellish also screams "Wait what's that mean? What's that mean?! STOP!!" which left me wondering myself.

If you have time to waste check out Saving Private Ryan vs Finding Nemo. It's funny and a lot less serious. Buuubbbllessss! Bubbbllless!!