Don't pray in these cases or during these times.

   

 Allah Almighty says in Aya (43) of Surat Alnisa' {O you who have believed! Do not approach the prayer while you are drunk until you know what you are saying, or in a state of Janabah except those passing through until you have bathed, but if you are ill or on a journey or anyone of you has come from the toilet or you have contacted women and you do not find water, so Perform Tayyammum with clean dust, and Wipe your faces and your hands, indeed, Allah is Oft-Pardoning, All-Forgiving}, so Allah forbade the believers from approaching the prayer while they are intoxicated until they know what they are saying in their prayer for the one who is intoxicated has confusion in recitation, and lacks contemplation and humility in his prayer, and that was before alcoholic drinks were completely prohibited as mentioned in Aya (90) of Surat Alma'idah {O you who have believed! Indeed, the intoxicants, the gambling, the stone altars, and the arrows are nothing but filth from the work of Satan, so Avoid it so that you may succeed}.

 And Allah forbade the believers from entering the mosque while they are in the state of Janabah except for those who pass through the mosque, and not to sit in it until they take a bath, and  there are three states of Janabah in which the prayer is prohibited until the whole body is washed with water, the first of which is in the case of sexual intercourse, the second is the case of menstruation or puerperium, and the third is ejaculation of water of a man or a woman, whether in a sexual dream or while awake, as Umm Salama reported: "Umm Sulaim went to the Messenger of Allah (PBUH) and said Messenger of Allah! Allah is not ashamed of the truth, Is bathing necessary for a woman when she has a sexual dream?, upon this the Messenger of Allah said yes, when she sees the liquid (Vaginal secretion), Umm Salama said Messenger of Allah! Does a woman have sexual dream?, He said let your hand be covered with dust, in what way does her child resemble her?" (Sahih Muslim 313 a).

 In addition, Allah's Messenger (PBUH) forbade praying when one feels drowsy and does not know what to say, for he must be active, humble, and thoughtful, and should not use times of fatigue and sleep for prayer, as Aisha, May Allah be pleased with her, narrated that Allah's Messenger (PBUH) said: "If one of you becomes drowsy while praying, let him sleep until the drowsiness leaves him. For if one of you prays while drowsy, he does not know; perhaps he will go to seek forgiveness and end up cursing himself" (Sahih Albukhari 212). And Allah's Messenger (PBUH) said in narration of Abu Hurayrah: "When any one of you gets up at night (for prayer), and his tongue falters in the recitation of the Quran, and he does not know what he is reciting, he should go to sleep" (Sahih Muslim 787). 

 As the prayer is prohibited in these cases, it is also prohibited in five times, as Amr bin Abasa Al-Sulami narrated hat Allah's Messenger said: "Observe the Dawn prayer, then Stop praying when the sun is rising till it is fully up, for when it rises, it comes up between the horns of Satan, and the disbelievers prostrate themselves to it at that time, then Pray, for the prayer is witnessed and attended (by Angels) till the shadow becomes about the length of a lance, then Cease prayer for at that time Hell is heated up, then when the shadow moves forward, Pray for the prayer is witnessed and attended (by Angels) till you pray the afternoon, then Cease prayer till the sun sets, for it sets between the horns of devil, and at that time, the disbelievers prostrate themselves before it" (Sahih Muslim 832). And in another narration of Abu Sa'id Alkhudri, Allah's Messenger (PBUH) said: "No prayer after two prayers: after the Fajr prayer till the sun rises, and after Asr prayer till the sun sets" (Sahih Albukhari 1197).

 And Al-Ala' bin Abdul-Rahman reported that they came to the house of Anas bin Malik in Basra after praying the Dhuhr prayer (Noon prayer), his house was situated by the side of the mosque, as revisited him, he said Have you pray the Asr prayer (Afternoon prayer)?, we said to him it is just a few minutes before that we finished the noon prayer, he said Offer the afternoon prayer, so we stood up and offered our prayer, and when we completed it, he said I have heard the Messenger of Allah (PBUH) saying: "This is how the hypocrite prays, he sits watching the sun, and when it is between the horns of devil, he rises and strikes the ground four times (in haste) mentioning Allah a little during it" (Sahih Muslim 622).

 Therefore, the five times when performing prayer is prohibited are: After the Fajr prayer until the sunrises, during the time of sunrise for fifteen minutes or more, before Dhuhr prayer when the shadow becomes about the length of a lance (about fifteen minutes before Dhuhr prayer), after Asr prayer until the sun sets, and during the time of sunset ( about fifteen minutes before Maghrib prayer).

 So one should not be lazy, neglecting to perform the prayer on time, and performing it at prohibited times lest his prayer be like the prayer of the hypocrites as shown above. But some prayers are exempt from this prohibition, including the obligatory prayers if a person forgets them or sleeps and does not perform them, so one should perform the missed prayer whenever he remembers it, as Anas bin Malik reported that Allah's Messenger (PBUH) said: "If anyone forgets a prayer, he should pray that prayer when he remembers it, there is no expiation except to pray it, then He (PBUH) recited {And Establish the prayer for My remembrance, Surat Ta Ha, Aya 14}" (Sahih Albukhari 597), and in another narration of Anas also, Allah's Messenger (PBUH) said: "He who forgets the prayer, or he slept, its expiation is only that he should observe it when he remembers it" (Sahih Muslim 684), also exempt from this prohibition are Friday prayer (Jumu'ah prayer), the eclipse prayer, the prayer for rain, the prayer of greeting the mosque, the two Rak'ahs of Tawaf, the prayer at the Sacred House of Mecca (Ka'bah) at all times.