Plurals in English are formed with ‘-s,’ as a rule. But this ‘s’ is sometimes pronounced as an ‘s’, sometimes as a ‘z.’ This might not be too obvious, but ‘clogs,’ ‘bangs’ and ‘whims’ all sound ‘z,’ even though they are spelled ‘s.’ ‘Laps,’ ‘hats’ and ‘clocks,’ on the other hand, sound ‘s.’
Unfortunately, the letter ‘z’ looks unfamiliar to readers of English. But, no compromise! So we are going to have ‘clogz,’ ‘bangz’ and ‘whimz.’ It’s ugly. Oh well.