1‘I was astonished at how much he had learned’
amaze, astound, stagger, surprise, startle, stun, confound, dumbfound, stupefy, daze, nonplus
throw, shake, unnerve, disconcert, discompose, bewilder
take someone's breath away, take by surprise, take aback, shake up, stop someone in their tracks, strike dumb, leave open-mouthed, leave aghast, catch off balance
informal flabbergast, floor, knock for six, knock sideways, knock out, knock the stuffing out of, bowl over, blow someone's mind, blow away
We take a look at several popular, though confusing, punctuation marks.