The word(s) "knew" appears 35 time(s) in 33 verse(s) in Quran in Mohsin Khan translation.

(21) The likeness of those who take (false deities as) Auliya' (protectors, helpers) other than Allah is the likeness of a spider who builds (for itself) a house; but verily, the frailest (weakest) of houses is the spider's house - if they but knew.

(22) And this life of the world is only an amusement and a play! Verily, the home of the Hereafter - that is the life indeed (i.e. the eternal life that will never end), if they but knew .

(23) And those who have been bestowed with knowledge and faith will say: "Indeed you have stayed according to the Decree of Allah, until the Day of Resurrection: so this is the Day of Resurrection, but you knew not."

(24) It was said (to him when the disbelievers killed him): "Enter Paradise." He said: "Would that my people knew

(25) So Allah made them to taste the disgrace in the present life, but greater is the torment of the Hereafter if they only knew!

(26) And you have not been hiding yourselves (in the world), lest your ears, and your eyes, and your skins should testify against you; but you thought that Allah knew not much of what you were doing.

(27) And thus We have sent to you (O Muhammad صلى الله عليه و سلم) Ruh (a Revelation, and a Mercy) of Our Command. You knew not what is the Book, nor what is Faith? But We have made it (this Qur'an) a light wherewith We guide whosoever of Our slaves We will. And verily, you (O Muhammad صلى الله عليه و سلم) are indeed guiding (mankind) to the Straight Path (i.e. Allah's Religion of Islamic Monotheism).

(28) Indeed, Allah was pleased with the believers when they gave the Bai'ah (pledge) to you (O Muhammad صلى الله عليه وسلم) under the tree: He knew what was in their hearts, and He sent down As-Sakinah (calmness and tranquillity) upon them, and He rewarded them with a near victory.

(29) Indeed Allah shall fulfil the true vision which He showed to His Messenger (صلى الله عليه وسلم) [i.e. the Prophet صلى الله عليه وسلم saw a dream that he has entered Makkah along with his Companions, having their (head) hair shaved and cut short] in very truth. Certainly, you shall enter Al-Masjid-al-Haram, if Allah wills, secure, (some) having your heads shaved, and (some) having your head hair cut short, having no fear. He knew what you knew not, and He granted besides that a near victory.

(30) Such is the punishment (in this life), but truly, the punishment of the Hereafter is greater if they but knew.