Nothing-saying

as a sentence ending particle gives a bit of a "y'know" vibe.

「タッタッタ」って車に乗ってみたい。 I really want a car that goes like 'tatata', y'know?

Wonder

denotes being hopeful, wondering if something will happen.

明日は晴れるかなあ I wonder, will the weather clear up tomorrow?

すごいなぁ That's amazing!