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

(21) Say: He has the power that He should send on you a chastisement from above you or from beneath your feet, or that He should throw you into confusion, (making you) of different parties; and make some of you taste the fighting of others. See how We repeat the communications that they may understand.

(22) And He it is Who has brought you into being from a single soul, then there is (for you) a resting-place and a depository; indeed We have made plain the communications for a people who understand.

(23) Say: Come I will recite what your Lord has forbidden to you-- (remember) that you do not associate anything with Him and show kindness to your parents, and do not slay your children for (fear of) poverty-- We provide for you and for them-- and do not draw nigh to indecencies, those of them which are apparent and those which are concealed, and do not kill the soul which Allah has forbidden except for the requirements of justice; this He has enjoined you with that you may understand.

(24) Then there came after them an evil posterity who inherited the Book, taking only the frail good of this low life and saying: It will be forgiven us. And if the like good came to them, they would take it (too). Was not a promise taken from them in the Book that they would not speak anything about Allah but the truth, and they have read what is in it; and the abode of the hereafter is better for those who guard (against evil). Do you not then understand?

(25) And certainly We have created for hell many of the jinn and the men; they have hearts with which they do not understand, and they have eyes with which they do not see, and they have ears with which they do not hear; they are as cattle, nay, they are in worse errors; these are the heedless ones.

(26) Surely the vilest of animals, in Allah's sight, are the deaf, the dumb, who do not understand.

(27) O Prophet! urge the believers to war; if there are twenty patient ones of you they shall overcome two hundred, and if there are a hundred of you they shall overcome a thousand of those who disbelieve, because they are a people who do not understand.

(28) They preferred to be with those who remained behind, and a seal is set on their hearts so they do not understand.

(29) And it does not beseem the believers that they should go forth all together; why should not then a company from every party from among them go forth that they may apply themselves to obtain understanding in religion, and that they may warn their people when they come back to them that they may be cautious?

(30) And whenever a chapter is revealed, they cast glances at one another: Does any one see you? Then they turn away: Allah has turned away their hearts because they are a people who do not understand.