Language history questionnaire (LHQ) is an important tool for assessing language learners' linguistic background, the context and habits of language use, proficiency in multiple languages, and the dominance and cultural identity of the languages acquired. Items in the LHQ included questions about the participants’ language history (e.g., age of second language acquisition and length of second language education), self-rated first- and second-language proficiency, and language usage in the home environment. LHQ3 allows researchers to assign different weights to the modules when calculating the aggregated scores, addressing the issue of different focuses that different researchers put on multilingual speakers’ language usage and background.