the four business units are the representative areas.

[keannu]

[FONT=&#48148]Korea is famous for its most developed IT business. Korea has many well-known companies such as LG and SK, but the most famous one is Samsung Electronics.
SEC is a united electronics company. It has semiconductor business, telecommunication business, home appliance business, and display business. It has more business units, but these four (business) units are the representative areas.[/FONT]
[FONT=&#48148]
Are the underlined correct?[/FONT]

 

[Tarheel]

LG -- Yep, that's my phone. (Powered by Android.)

What's a united electronics company?

What's a business unit? A company?

 

[keannu]

LG -- Yep, that's my phone. (Powered by Android.)

What's a united electronics company? "united" means "general - comprehensive"

What's a business unit? A company?

"business sections or divisions that comprise the whole company" - sub-parts of one big company.

 

[tedmc]

united - integrated? diversified?
representative areas - core areas? mainstay?

 

[Tarheel]

Korea is famous for its IT businesses.

SEC is a diversified electronics company.

Those business units are the key areas.

(My shot.)