用作定语
▲～+n.
 She is an efficient manageress.她是一个有能力的经理。
用作表语
▲S+be+～
 This machine is efficient.这台机器效率高。
▲S+be+～+prep.-phrase
 She was very efficient in reducing waste.她在减少浪费方面很有办法。

efficient, effective, effectual, efficacious
参见effective条。

［同义词］    competent, effective, useful, able
［反义词］   ineffective, useless