小剂量服用时，这种药物是完全无害的。

This medicine is ___harmless when taken in small doses.

许多人认为汽车本质上无害，但这并不完全正确。

Many people believe that cars are essentially ___harmless, but this isn't entirely true.

我们的宠物兔子很温顺，完全无害。

Our pet rabbit is gentle and completely ___harmless.