minnanihongo.com/courses/speed-master-n4-grammar
A structured online course with 33 grammar lessons aligned to the Speed Master textbook series, covering essential N4 grammar points with explanations and practice for JLPT preparation.
GrammarJLPT and other testsJLPT N4Sentence patternsJLPTFreeConditionalsPassive and causativeTransitive and intransitive