Something I wrote to a student of mine:
‘Arabic grammar on its own is not sufficient. You need to widen your reading to include: Arabic grammar, prose and poetry. I’ll give you list of some books I recommend on each below.
Sharh Shudhoor al-Dhahab by Ibn Hisham
Alfiyya ibn Malik with its various commentaries – I recommend the one by Ibn Aqeel and edited by Ahmad Shirbasy.
For more on the theoretical side of grammar read – Sharh Jami this is a commentary on Ibn Hajib’s famous Kafiya. This is highly theoretical and uses a lot of mantiq terminology.
For English sources on grammar the best source that I’ve found is Wright’s Grammar. But this is of more use as a reference book.
For practical exercises on grammar try A New Arabic Grammar by Nahmad & Haywood.
By prose I mean the actual application of grammar. And using different styles and expressions to convey meaningful sentences. There are a great number of anthologies available. I recommend the following:
Mukhtarat min Adab al’Arab by Abul Hasan Nadwi
Mukhtarat by Ali Tantawi
Generally speaking I would recommend all works by the above two authors. They have great literary style. I particularly like the latter as he combines French literary style to the archaic Arabic one.
The above two books will also introduce you to many other authors who are included in the anthologies. And also give you an insight into the historical change in literary style in each subsequent era – early Islamic, Umayyad, Abbasid and modern.
Suwar min Hayat al-Sahabah by Abdur Rahman Rafat Pasha is also very good.
You need to take your time with poetry. Poems need to be read slowly and over and over again out aloud for it to really move you from your inner core. A good place to start would be Abul Itahiya and Abu Nawwas. But you ultimately will need to face Mutanabbi and Abu Tamam’s Hamasah.
To get a better appreciation of the Quran’s style you need to go to the pre-Islamic poets. The Sab’a Muallaqat are indispensable in this regard. I spent a whole Ramadan reading one of the mu’allaqahs a few years ago, and I was amazed at the affect it had on my Quranic understanding.
There is also another genre which is rhymed prose – maqamat in Arabic. This was style developed in the late Abbasid era and gained prominence as it enabled the author to show his literary prowess. Good examples of this are in Hariri’s Maqamat and Hamdhani’s Maqamat.
If you want to know about the historical development than Ibn Khaldun’s Muqaddimah’s section on this is a good place to start (this has a very good translation into English by Franz Rosenthal and is available online). Siddiq Hasan Khan’s Abjad al-Uloom also gives a good overview of the historical development of grammar.
That should suffice you for now.’