KJV:
Say not ye, There are yet four months, and then cometh harvest? behold, I say unto you, Lift up your eyes, and look on the fields; for they are white already to harvest.
NASB:
"Do you not say, 'There are yet four months, and then comes the harvest '? Behold, I say to you, lift up your eyes and look on the fields, that they are white for harvest.