助动词- _$ A" m$ a+ h4 V
助动词没有独立的语义，主要作用是协助谓语动词表示时态、语态或构成疑问式、否定式等 7 V% p6 A, o5 y4 A0 y. X1 P2 I' m
助动词和情态动词的共同特点是需要和其他动词搭配使用才有意义，而且句子的否定式和疑问式都可通过这两类词体现
% E+ W5 z6 y4 r) T 一、have/has (现在完成时), had (过去完成时) 2 a& X3 ^% T+ `4 ~5 _+ U
这组助动词主要用来构成完成时态，形式为：have /has /had + 过去分词
9 v0 J3 U1 ^8 h5 P 如：I haven’t seen you for ages.
2 ^, G( A+ o0 W2 ~0 W" H( M She had mentioned this before. 7 N5 `3 c |* c5 L8 a
二、be / |8 E# S) K- ]2 n
be本身可作谓语动词，但在进行时中它是助动词，与现在分词搭配使用，缺一不可 9 A( R3 t8 c/ D2 D
如：She’s watching a football match.
; {/ d3 N$ U5 \- D He’s looking for his favorite pet.
! w% [2 a/ B. S6 l8 v 此外，be和过去分词搭配构成被动语态
& P# O" [" A$ e% S! `) k X/ N. g 如：The vicar was killed in a car accident. : S# i8 m* V0 r0 g0 {. H+ }4 d
三、do/does (一般现在时), did (一般过去时) - o9 |, m0 e0 D% ]0 \$ o# M5 O
此组助动词用于构成疑问式或否定式 " m0 S9 C5 e$ V9 G* r" |6 z7 C
如：He doesn’t feel like smoking at the moment.
: \7 p" I9 |) Q2 T Did you meet the manager this morning? ! H* p( y2 Z; Y5 g, p, z/ W
四、will, shall, would
- ^$ q& H( L2 K) S) R 此组助动词用于构成将来时 + ~" d% P8 M( J7 _! F* j3 t
如：He won’t be able to see you until an hour later.
: k5 g; E, E U A% m Mary promised she would pay you a visit soon.
2 s6 r+ f" U$ q$ `* o1 b0 M4 U 例题： Q9 s- Y8 m/ K2 p3 f( `
(1)
0 f( _5 `( p1 o$ I0 o, Q/ ~ The colors of a rainbow ---- arranged in the same order. 5 I& O& @/ S5 Y6 n1 l" E! o
(A) which are always 3 \9 t, r, C! Z2 R. E
(B) and they are always
* T% `; Y) M5 m8 n. Q (C) always - T# K$ {4 }5 g. ]0 x$ ^0 I5 E4 A
(D) are always 3 V1 R2 E( J q8 o5 \$ Y
答案：D
) p0 `: Q- X8 h 解释：空格前是句子的主语，之后是过去分词短语，空格处需要补全句子的谓语，A使原句只有从句无主句；B并列句的前一个分句无谓语；arrange与color是被动关系，C是主动式，可排除；只有D助动词are恰好与arranged构成句子的谓语 |
发表于 2012-8-14 23:32:39
