Verses with the word plainly in the Old Testament (6 verses):

Exodus 21:5
And if the servant shall plainly say, I love my master, my wife, and my children; I will not go out free:

Deuteronomy 27:8
And thou shalt write upon the stones all the words of this law very plainly.

1 Samuel 2:27
And there came a man of God unto Eli, and said unto him, Thus saith the LORD, Did I plainly appear unto the house of thy father, when they were in Egypt in Pharaoh's house?

1 Samuel 10:16
And Saul said unto his uncle, He told us plainly that the asses were found. But of the matter of the kingdom, whereof Samuel spake, he told him not.

Ezra 4:18
The letter which ye sent unto us hath been plainly read before me.

Isaiah 32:4
The heart also of the rash shall understand knowledge, and the tongue of the stammerers shall be ready to speak plainly.