The word(s) "proper" appears 23 time(s) in 21 verse(s) in Quran in Saheeh International translation.

(1) There is no blame upon you for that to which you [indirectly] allude concerning a proposal to women or for what you conceal within yourselves. Allah knows that you will have them in mind. But do not promise them secretly except for saying a proper saying. And do not determine to undertake a marriage contract until the decreed period reaches its end. And know that Allah knows what is within yourselves, so beware of Him. And know that Allah is Forgiving and Forbearing.

(2) And give to the orphans their properties and do not substitute the defective [of your own] for the good [of theirs]. And do not consume their properties into your own. Indeed, that is ever a great sin.

(3) And do not give the weak-minded your property, which Allah has made a means of sustenance for you, but provide for them with it and clothe them and speak to them words of appropriate kindness.

(4) And test the orphans [in their abilities] until they reach marriageable age. Then if you perceive in them sound judgement, release their property to them. And do not consume it excessively and quickly, [anticipating] that they will grow up. And whoever, [when acting as guardian], is self-sufficient should refrain [from taking a fee]; and whoever is poor - let him take according to what is acceptable. Then when you release their property to them, bring witnesses upon them. And sufficient is Allah as Accountant.

(5) Indeed, those who devour the property of orphans unjustly are only consuming into their bellies fire. And they will be burned in a Blaze.

(6) And [also prohibited to you are all] married women except those your right hands possess. [This is] the decree of Allah upon you. And lawful to you are [all others] beyond these, [provided] that you seek them [in marriage] with [gifts from] your property, desiring chastity, not unlawful sexual intercourse. So for whatever you enjoy [of marriage] from them, give them their due compensation as an obligation. And there is no blame upon you for what you mutually agree to beyond the obligation. Indeed, Allah is ever Knowing and Wise.

(7) Among the Jews are those who distort words from their [proper] usages and say, "We hear and disobey" and "Hear but be not heard" and "Ra'ina," twisting their tongues and defaming the religion. And if they had said [instead], "We hear and obey" and "Wait for us [to understand]," it would have been better for them and more suitable. But Allah has cursed them for their disbelief, so they believe not, except for a few.

(8) So for their breaking of the covenant We cursed them and made their hearts hard. They distort words from their [proper] usages and have forgotten a portion of that of which they were reminded. And you will still observe deceit among them, except a few of them. But pardon them and overlook [their misdeeds]. Indeed, Allah loves the doers of good.

(9) O Messenger, let them not grieve you who hasten into disbelief of those who say, "We believe" with their mouths, but their hearts believe not, and from among the Jews. [They are] avid listeners to falsehood, listening to another people who have not come to you. They distort words beyond their [proper] usages, saying "If you are given this, take it; but if you are not given it, then beware." But he for whom Allah intends fitnah - never will you possess [power to do] for him a thing against Allah. Those are the ones for whom Allah does not intend to purify their hearts. For them in this world is disgrace, and for them in the Hereafter is a great punishment.

(10) And do not approach the orphan's property except in a way that is best until he reaches maturity. And give full measure and weight in justice. We do not charge any soul except [with that within] its capacity. And when you testify, be just, even if [it concerns] a near relative. And the covenant of Allah fulfill. This has He instructed you that you may remember.