slippery, slide, slip, fail exam

Radicals

• 円滑【えんかつ】
  smooth, undisturbed, uninterrupted, harmonious
• 滑らか【なめらか】
  smooth (of a surface), glassy, velvety, soft, smooth (of an action, proceedings, etc.), fluent (speech), fluid, trouble-free, continuously differentiable
• 滑稽【こっけい】
  funny, comical, humorous, laughable, ridiculous, silly, absurd