长 is a common word in Chinese language. It can be used as a verb, a noun and an adjective. Do you know when to read chánɡ and when to read zhǎnɡ?
长 is usually pronunced as chánɡ at four conditions and with four different meanings:
1). (as a noun) it means the length between two points, such as “长度（chánɡ dù）, 长短(chánɡ duǎn)
2). (as a adjective) it is oppositive to short and can be used to describe the time and space, such as 长空（chánɡ kōnɡ），长夜（chánɡ yè）.
3). (as a noun) it means advantage and speciality, such as 特长(tè chánɡ), 专长(zhuān chánɡ).
4). (as a verb) it means “be good at”, such as 擅长(shàn chánɡ).
长 is usually pronunced as zhǎnɡ at five conditions and with five different meanings:
1). (as a verb) it means “grow”, such as 成长(chénɡ zhǎnɡ) and 长大(zhǎnɡ dà).
2). (as a verb) it means “increase”, such as 长知识(zhǎnɡ zhī shi).
3). (as a adjective) it is used to describe something or somebody ranking first, like 长子(zhánɡ zǐ), 长孙(zhǎnɡ sūn).
4). (as a adjective) it is used to describe somebody that is older, such as 长辈(zhǎnɡ bèi), 家长(jiā zhǎnɡ).
5). (as a noun) it is used to decribe the leader or someone on charge of something, such as 部长(bù zhǎnɡ), 校长(xiào zhǎnɡ).
Now do you know how to say long, be good at in Chinese, and when to read chánɡ and zhǎnɡ?You can leave me messages via my facebook page @chinesecultureandlanguage if you have any questions about Chinese language or culture.