The word(s) "understand" appears 86 time(s) in 86 verse(s) in Quran in Muhammad Habib Shakir translation.

(11) O followers of the Book! why do you dispute about Ibrahim, when the Taurat and the Injeel were not revealed till after him; do you not then understand?

(12) O you who believe! do not take for intimate friends from among others than your own people; they do not fall short of inflicting loss upon you; they love what distresses you; vehement hatred has already appeared from out of their mouths, and what their breasts conceal is greater still; indeed, We have made the communications clear to you, if you will understand.

(13) Most surely in the creation of the heavens and the earth and the alternation of the night and the day there are signs for men who understand.

(14) And do not give away your property which Allah has made for you a (means of) support to the weak of understanding, and maintain them out of (the profits of) it, and clothe them and speak to them words of honest advice.

(15) Wherever you are, death will overtake you, though you are in lofty towers, and if a benefit comes to them, they say: This is from Allah; and if a misfortune befalls them, they say: This is from you. Say: All is from Allah, but what is the matter with these people that they do not make approach to understanding what is told (them)?

(16) And when you call to prayer they make it a mockery and a joke; this is because they are a people who do not understand.

(17) Say: The bad and the good are not equal, though the abundance of the bad may please you; so be careful of (your duty to) Allah, O men of understanding, that you may be successful.

(18) Allah has not ordained (the making of) a bahirah or a saibah or a wasilah or a hami but those who disbelieve fabricate a lie against Allah, and most of them do not understand.

(19) And of them is he who hearkens to you, and We have cast veils over their hearts lest they understand it and a heaviness into their ears; and even if they see every sign they will not believe in it; so much so that when they come to you they only dispute with you; those who disbelieve say: This is naught but the stories of the ancients.

(20) And this world's life is naught but a play and an idle sport and certainly the abode of the hereafter is better for those who guard (against evil); do you not then understand?