The best app for learning English is free.

The best apps for learning English are Duolingo, Memrise, Anki and BBC to learn English for free.

Data expansion:

BBC learning English is a good software; The best apps for learning English are HelloTalk, LingQ and Engoo. English learning software recommends BBC Learning English, which provides many free learning resources, including news, video, audio and online courses.

English vocabulary is huge (about 990 thousand words), but to estimate the specific figures, we must first judge which words can be counted as it. However, unlike other languages, there is no authoritative academic institution to define what is a formal vocabulary.

New words in the fields of medicine, science and technology are constantly emerging, some of which have entered the daily language of the public, and some are only used in a small range of people. Foreign language words brought by immigrant groups tend to blend into the English-speaking society. It is impossible to judge whether some ancient words and dialect words can be counted as English.

The Oxford English Dictionary (Second Edition) contains more than 500,000 entries, and the standard is relatively loose: "It includes standard words in literature and daily conversation, whether contemporary, outdated or archaic, as well as major scientific and technological words and a large number of dialects and slang."

Since the popularization of electronic computers, many words related to this category have entered the public life; In addition, many new words related to telecommunication technology are composed of affixes.

For example, "wiki" itself is Hawaiian, but because of the popularity of Wikipedia, "Wikify" (wiki+-fy, meaning wikization) has emerged; Then "wikify" (the process or action of wikify) came into being from wikify.

In addition, a new word "serializability" used in the database means "feasibility of streaming data to be written into the database", which itself comes from another new word "serialize" (streaming data to be written into the database comes from "serial", that is, streaming).