Al-Jazeera offers a grammar test. There are a couple of pitfalls. So, reason enough to take a look at the most important Arabic grammar topics.
Adjectives in Egyptian Arabic can be tricky. Sometimes you need to form the plural. An overview of the most common plural patterns of Egyptian adjectives.
The Arabic broken plural has the effect that scholars still debate how to properly classify the several branches of Semitic languages.
The plural of Mustafa in Arabic is difficult - because there is a weak letter involved. How do you form masculine human plurals with a possessive pronoun?