Misplaced Modifier - In these types of questions, phrases are mostly misplaced, illogically placed or describes some incorrect words.
Verb-subject Compatibility - GMAT sentence correction questions frequently cover verb-subject errors. The nature of the sentence must match the verb.
Idioms - GMAT sentence correction is more than correcting grammatical mistakes, it involves sentence creation that should sound idiomatically correct also.
Countable and Uncountable - GMAT sentence correction questions comprise of phrases which are used to measure your critical thinking in terms of putting situations with countable and uncountable things . Uncountable things include the much less amount with singular nouns.
Parallelism - GMAT sentence improvement questions include some parallelism related things. Such as sentences consisting of frequently repeating nouns, verbs and phrases.
Paired Words - GMAT sentence correction questions consist of questions related to pairing and construction of sentences.