For certain and Laboriously

For certain adverb - Definitely or positively (`sure' is sometimes used informally for `surely').

Laboriously and for certain are semantically related. In some cases you can use "Laboriously" instead an adverb phrase "For certain".

Laboriously adverb - In a manner involving great or constant activity.

For certain and laboriously are semantically related. Sometimes you can use "For certain" instead an adverb "Laboriously".