(50:40) And [in part] of the night exalt Him and after prostration.
Muhammad Taqi-ud-Din al-Hilali and Muhammad Muhsin Khan,
(50:40) And during a part of the night (also), glorify His praises (i.e. Maghrib and ‘Isha prayers), and (so likewise) after the prayers [As-Sunnah, Nawafil optional and additional prayers, and also glorify, praise and magnify Allah – Subhan Allah, Alhamdu lillah, Allahu-Akbar].
Mohammed Marmaduke William Pickthall
(50:40) And in the night-time hymn His praise, and after the (prescribed) prostrations.
Abdullah Yusuf Ali
(50:40) And during part of the night, (also,) celebrate His praises, and (so likewise) after the postures of adoration.
Mohammad Habib Shakir
(50:40) And glorify Him in the night and after the prayers.
Dr. Ghali
(50:40) And in the night then extol (Him) and at the ends (Literally: at the rear) of prostrations.
Ali Unal
(50:40) And during (some part of) the night, too, glorify Him, and after the prostrations.
Amatul Rahman Omar
(50:40) And celebrate His praises during parts of the night and after (prescribed) prostrations (in your Prayers).
Literal
(50:40) And from the night so praise/glorify Him, and (during) the prostration`s ends/backs.
Ahmed Ali
(50:40) And glorify Him for some portion of the night, and additional adorations.
A. J. Arberry
(50:40) and proclaim thy Lord’s praise in the night, and at the ends of the prostrations.
Abdul Majid Daryabadi
(50:40) And in the night-time hallow Him, and also after the prescribed prostration.
Maulana Mohammad Ali
(50:40)-
Muhammad Sarwar
(50:40) Glorify Him during the night and also glorify Him after prostration.
Hamid Abdul Aziz
(50:40) And glorify Him in the night and after the prescribed prostrations.
Faridul Haque
(50:40) And say His Purity during the night, and after the customary prayers.
Talal Itani
(50:40) And glorify Him during the night, and at the end of devotions.
Ahmed Raza Khan
(50:40) And say His Purity during the night, and after the customary prayers.
Wahiduddin Khan
(50:40) proclaim His praise in the night and at the end of every prayer.
Safi-ur-Rahman al-Mubarakpuri
(50:40) And during a part of the night (also) glorify His praises and (so likewise) after the prostrations.
Ali Quli Qarai
(50:40) and glorify Him through part of the night and after the prostrations.
Hasan al-Fatih Qaribullah and Ahmad Darwish
(50:40) And exalt Him in the night, and at the ends of the prostrations.
That is translated surah Qaf ayat 40 (QS 50: 40) in arabic and english text, may be useful.