The word(s) "regular" appears 65 time(s) in 45 verse(s) in Quran in Abdullah Yusuf Ali translation.

(41) Those who practise not regular Charity, and who even deny the Hereafter.

(42) Those who hearken to their Lord, and establish regular Prayer; who (conduct) their affairs by mutual Consultation; who spend out of what We bestow on them for Sustenance;

(43) Is it that ye are afraid of spending sums in charity before your private consultation (with him)? If, then, ye do not so, and Allah forgives you, then (at least) establish regular prayer; practise regular charity; and obey Allah and His Messenger. And Allah is well-acquainted with all that ye do.

(44) Thy Lord doth know that thou standest forth (to prayer) nigh two-thirds of the night, or half the night, or a third of the night, and so doth a party of those with thee. But Allah doth appoint night and day in due measure He knoweth that ye are unable to keep count thereof. So He hath turned to you (in mercy): read ye, therefore, of the Qur'an as much as may be easy for you. He knoweth that there may be (some) among you in ill-health; others travelling through the land, seeking of Allah's bounty; yet others fighting in Allah's Cause, read ye, therefore, as much of the Qur'an as may be easy (for you); and establish regular Prayer and give regular Charity; and loan to Allah a Beautiful Loan. And whatever good ye send forth for your souls ye shall find it in Allah's Presence,- yea, better and greater, in Reward and seek ye the Grace of Allah: for Allah is Oft-Forgiving, Most Merciful.

(45) And they have been commanded no more than this: To worship Allah, offering Him sincere devotion, being true (in faith); to establish regular prayer; and to practise regular charity; and that is the Religion Right and Straight.