(21:20) They exalt [Him] night and day [and] do not slacken.
Muhammad Taqi-ud-Din al-Hilali and Muhammad Muhsin Khan,
(21:20) They (i.e. the angels) glorify His Praises night and day, (and) they never slacken (to do so).
Mohammed Marmaduke William Pickthall
(21:20) They glorify (Him) night and day; they flag not.
Abdullah Yusuf Ali
(21:20) They celebrate His praises night and day, nor do they ever flag or intermit.
Mohammad Habib Shakir
(21:20) They glorify (Him) by night and day; they are never languid.
Dr. Ghali
(21:20) They extol (Him) by night and by daytime (and) they do not flag.
Ali Unal
(21:20) They glorify Him by night and day (proclaiming that He is absolutely exalted above any shortcoming or need of partners or doing pointless things), and never show tiredness and never lose zeal.
Amatul Rahman Omar
(21:20) They glorify (Him) night and day (and) they flag not.
Literal
(21:20) They praise/glorify (during) the night and the daytime, they do not subside/abate .
Ahmed Ali
(21:20) Nor cease to endeavour praising Him night and day.
A. J. Arberry
(21:20) glorifying Him by night and in the daytime and never failing.
Abdul Majid Daryabadi
(21:20) And they hallow Him night and day, and they flag not.
Maulana Mohammad Ali
(21:20)-
Muhammad Sarwar
(21:20) They glorify Him day and night without fail.
Hamid Abdul Aziz
(21:20) Unto Him belongs whoever is in the heavens and the earth, and those who dwell in His Presence are not too proud to serve Him, nor do they weary.
Faridul Haque
(21:20) They say His Purity night and day, and do not slacken.
Talal Itani
(21:20) They praise night and day, without ever tiring.
Ahmed Raza Khan
(21:20) They say His Purity night and day, and do not slacken.
Wahiduddin Khan
(21:20) they glorify Him night and day without tiring.
Safi-ur-Rahman al-Mubarakpuri
(21:20) They glorify His praises night and day, they never slacken.
Ali Quli Qarai
(21:20) They glorify [Him] night and day, and they do not flag.
Hasan al-Fatih Qaribullah and Ahmad Darwish
(21:20) They never fail to exalt Him either at night or in the day.
That is translated surah Al Anbiya ayat 20 (QS 21: 20) in arabic and english text, may be useful.
Yusabbihoona allayla waalnnahara la yafturoona
