Forth is one of those words that has gone out of the language except in a number of set phrases. When any work is to be done without any delay or hesitation and with no time intervening , Forthwith is used.
Meanings of Forthwith:
immediately; at once; without delay
Master’s Tip to Learn Forthwith:
Necessarily, if you go forth with others, you go at the same time as they do.
Sentence examples for Forthwith:
1. The court ordered the company to cease operations forthwith
2. If the fire alarm rings, leave the building forthwith.
3. an official accused of dishonesty should be suspended forthwith