The card should carry a root and a pattern rather than a word, because most Arabic words are generated and a generated word learned as an item is a fact you did not need to store. Learn that maf'al makes a place and every root you own gains a noun for free. Learn fa'il makes the one who does it and they all gain another.
The system is generous enough that the interesting question becomes the opposite one: which words are not derivable. That list is shorter than the derivable one and it is where the actual memorisation lives.
Two roots, and the grid they fill
Learning a root and a pattern is worth more than learning ten unrelated words, because the pattern applies to every root you will ever meet.
- k-t-b gives kitab, maktab, maktaba, katib, a book, an office, a library, a writer.
- d-r-s gives darasa, dars, madrasa, mudarris, he studied, a lesson, a school, a teacher.
- maf'al is a place. The pattern that produced maktab and madrasa produces a place associated with the root, every time.
- fa'il is a doer, giving katib from writing and talib, a student, from seeking.
- maktaba is a library or a bookshop, the place pattern with the feminine ending, and it sits one letter away from the office.
- mudarris is a teacher, from a different doer pattern used with derived verb forms, which is the second grid worth learning.
The plural is the hole in the system
Arabic has two ways of making a plural and only one of them is regular. The sound plural adds an ending and behaves. The broken plural rearranges the word internally, pouring the same root into a different pattern, and which pattern a given noun takes cannot be derived from anything. Kitab becomes kutub. Bayt becomes buyut. Rajul becomes rijal.
There are perhaps two dozen broken plural patterns and no rule assigns them, so every noun arrives with its plural attached or with a permanent gap where the plural should be. This is the single most important thing to decide about your cards in the first week, because a deck of several hundred singular nouns is a deck that will fail the moment you talk about more than one of anything.
The other undeductive layers are smaller and worth naming. Borrowings do not follow the patterns and behave like foreign words. A number of very common words are frozen forms whose root is not recoverable in practice. And the dialect vocabulary is a separate list that overlaps the standard rather than deriving from it.
Deriving everything and owning no plurals
Here is the stall, and it is created by the system working. A learner takes the root and pattern method seriously, builds vocabulary quickly, and reads well. Then they try to say something about two books or several offices and stop, because the singulars were derived and the plurals were not derivable and were therefore never stored.
It is invisible until production starts, which for most learners is months later, and by then the deck is large and adding a plural to every existing card is a job nobody does. The fix has to be a rule about future cards plus a triage of the frequent existing ones, in that order. Every noun from today carries its plural; the two hundred nouns you use most get theirs added this week; the rest get corrected as they surface. That triage is the same one that applies to Russian stress and to German gender, and the reasoning behind it is in making cards that teach rather than cards that pile up.
Before adding a card
Does this word need storing, or was it already yours
The test takes a few seconds and it removes a large share of what most Arabic decks are carrying.
Is this a real item, or a pattern you already own
- NoIt falls out of a root and pattern you knowLearn the pattern once and drop the wordNo
- YesIt is a noun, and you have its pluralWithout the plural the card fails at productionYes
- YesIt is a verb, with its form number and prepositionNeither is derivable from the rootYes
- YesIt is a borrowingOutside the system, so it is an ordinary vocabulary itemYes
- Not checkedWhether you will meet it again this yearThe one nobody can answer, and everybody guesses atNot checked
The last row is genuinely unknown rather than merely uncertain: frequency data for Arabic is thinner than for the big European languages, so a learner deciding whether a word is common is usually guessing with less to go on than they think.
Two things to build the cards from
Anki is the tool and the decision that matters is what goes on the front. For a noun that is the word, its plural and its root; for a verb it is the form number and the preposition it takes. It replaced the vocabulary list with the plural in a column, which stores two facts about one word instead of one item. Free on desktop and Android, paid once on iOS. Nothing in a shared deck will enforce this, so it has to be a habit rather than a setting.
Wiktionary is the free lookup that gives you all of it at once: the root, the form, the broken plural and the vowelled pronunciation, on one page and without needing to identify the root first. It replaced the root-ordered dictionary for the specific job of building a card, which is a different job from reading, since the root dictionary refuses to answer until you have already done the analysis.
The mistake: collecting words the system would have given you
A deck full of derived nouns is a deck full of items that could have been read off a pattern. Maktab, maktaba, katib, maktub and kitaba are five cards or they are one root and four patterns, and the second version also covers the hundreds of other roots those patterns apply to.
The test before adding anything is whether the word falls out of a root and a pattern you already own. If it does, learn the pattern once and drop the word. If it does not, it is a real item and it belongs on a card with everything it cannot supply for itself. Applied honestly this removes a large share of what most learners are reviewing, and it moves the saved time to the two places the system does not reach, which are the plurals and the spoken vocabulary in which to learn first, and what each is used for.
What the root gives and what it does not
A root gives a field of meaning rather than a meaning, so the pattern has to be identified before the word can be read at all, and that machinery is three letter roots, and patterns that generate the vocabulary. The consonants that carry the root are also the ones with no English equivalent, so a root heard and a root read are different acquisitions, which is the throat sounds, and the emphatic consonants. Identifying a root on the page depends on the letters being invisible, in right to left, joined letters, and vowels you infer. And the words that make up ordinary speech are largely a different set from the ones on this page, which is news Arabic, and the Arabic people actually speak.