语法精讲Word Formation:Compounds构词法：合成
合成：把两个或两个以上的词合成一个新词，有的用连字符号“”连接，有的直接连写在一起，还有的由分开的两个词构成，这种构词法叫合成。
1.合成名词的主要构成方式
(1)n.+n. classroom newspaper schoolboy
(2)adj.+n. blackboard greenhouse highway
(3)v.+n. chopstick
(4)adv.+n. overcoat
(5)v.+adv. breakdown gettogether
(6)n.+prep. sisterin-law editorin-chief
2.合成形容词的主要构成方式
(1)n.+adj. snowwhite worldwide
(2)adj.+adj. redhot
(3)adv.+adj. evergreen
(4)n.+doing/done manmade earthshaking
(5)adj.+doing/done readymade goodlooking
(6)adv.+doing/done wellinformed
(7)adv.+n. secondhand
(8)adj.+n.-ed whitehaired absentminded
(9)num.+n.-ed threehaired oneeyed
3.合成动词的主要构成方式
adv.+v.overcome overlook
4.合成副词的主要构成方式
adj.+n. meanwhile
prep.+n.beforehand
【考例1】 It is a _______ dog,16 or 17 inches tall from the shoulder.
A.middle size
B.middle-size
C.mid-sized
D.middle-sized
解析：middle-sized adj. “中等大小的”。
答案：D
【考例2】Walking and running are the oldest and the best excellent ________ exercise for all ages and fitness levels.
A.bodies-shaping
B.body-shape
C.bodies-shaped
D.body-shaping
解析：选项在句中作定语，且表示exercise的用途，指的是塑身的运动，故选用动词-ing形式。
答案：D
【考例3】If you go _________,you might find a stream.
A.downhill
B.downhills
C.down-hill
D.down-hills
解析：由句子结构可知，需要一个副词来修饰不及物动词go,故选择downhill。
答案：A
【考例4】 Films often present the image of a _________ and intelligent lawyer standing in court and winning arguments.
A.well-speak
B.well-speaking
C.well-spoken
D.well-talk
解析：spoken构成合成词时，表示“说话有……特点的”，与副词连用。
答案：C