Allahuma ya muqaliba al-quloob thabit qalbi ‘ala deenika
اللهم يا مُقلِّبَ القُلوب … ثبتْ قَلبي على دينكَ
Rule Three: Iqlaab — Tahweel Al-shay’ ‘an wajh (Flipping).
After every Noon Saakinah or Tanween, if the letter baa (?) follows, the sound must be flipped [i.e. changed] to the sound of the letter meem (?). This is represented by a little meem on top of the letter itself as pictured below:
The lips should not be entirely pressed together, to allow for the meem to come through the nasal passage as well. The mouth should be prepared to say the baa after sounding through the meem. So the above, min b‘ad is sounds like mimm b‘ad when read. What ever you do, take this piece of advice and do not get mixed up between the full shaped meem (م) drawn above letters to indicate iqlaab, and the cut meem (مـ) to indicated a compulsory stop. Refer to the resources link below. Iqlaab must be sounded for two counts, i.e. the time it takes to say the words, “one – two”.
Examples of the third rule are as follow:
example one: min b‘ad – منْ بَعْدِ
example two: layunbathanna – لَيُنْبِذَنَّ
example three: samee‘an baseeran – سَمِيعَاً بَصِيراً
– Sukoon [Gateway to Arabic, page 48]
– Rules of stopping [Tajweed Basics: Foundations and More: page 15]
– Tanween [Gateway to Arabic: page 40]
[Tajweed Basics: Foundations and More: pages 11 – 14]
More about the Arabic letters can be found here: http://www.meem.freeuk.com/ scroll down to the “ABJAD TABLE” and select a letter.