Surah 43. Az-Zukhruf, Ayah 11

The grammatical form nazzala implies here recurrence: hence, "again and again".

In due measure: i.e., according to needs, as measured by local as well as universal considerations. This applies to normal rainfall: floods and droughts are abnormal conditions, and may be called unusual manifestations of His power, fulfilling some special purpose that we may or may not understand.

The clause 'And We raise...(from the dead)' is parenthetical. Cf. xxxv. 9, n. 3881. Note the transition from the third to the first person, to mark the Resurrection as a special act of Allah as distinguished from the ordinary processes of nature ordained by Allah.