Medieval Hebrew has many features that distinguish it from older forms of Hebrew. These affect grammar, syntax, sentence structure, and also include a wide variety of new lexical items, which are usually based on older forms.In the Golden age of Jewish culture in Spain important work was done by grammarians in explaining the grammar and vocabulary of Biblical Hebrew; much of this was based on the work of the grammarians of Classical Arabic. Important Hebrew grammarians were Judah ben David Hayyuj and Jonah ibn Janah. A great deal of poetry was written, by poets such as Dunash ben Labrat, Solomon ibn Gabirol, Judah ha-Levi and the two Ibn Ezras, in a "purified" Hebrew based on the work of these grammarians, and in Arabic quantitative metres (see piyyut). This literary Hebrew was later used by Italian Jewish poets.
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