B2 由…组成，由…构成
to be formed from various things
Air is composed mainly of nitrogen and oxygen. 空气主要由氮和氧构成。
The committee is composed of MPs, doctors, academics, and members of the public. 委员会由议员、医生、学者和普通民众组成。
The audience was composed largely of young people. 观众中大部分都是年轻人。
The mixture is composed of soy, peanuts, sugar, and oil.
The test is composed of two sections: written and practical.
See also: compose (FORM)