back, backward, hind, behind

形容詞 backward:

1. directed or facing toward the back or rear
2. (used of temperament or behavior) marked by a retiring nature
3. retarded in intellectual development
   同義詞：feebleminded

副詞 backward:

1. at or to or toward the back or rear
   同義詞：back, backwards, rearward, rearwards
2. in a manner or order or direction the reverse of normal
   同義詞：backwards
3. in or to or toward a past time
   同義詞：back

1. This part of the country is still backward.
   這個國家的這個地區(qū)仍很落后。
2. Although he is clever, he is backward in giving his views.
   他雖然很聰明，卻不善發(fā)表他的意見。
3. He looked backward over his shoulder.
   他回頭向后看。

back.ward

adj.（形容詞）
Directed or facing toward the back or rear.
向后的：指向或面向后邊或后部的
Done or arranged in a manner or an order that is opposite to previous occurrence or normal use.
逆向的：以和先前的情況或正常的用法相反的方式或順序來完成或安排的
Unwilling to act; reluctant; shy.
不愿做的；不情愿的；羞澀的
Behind others in progress or development:
落后的：在進程或發(fā)展上落后于其它人的：
例句：
The technology was backward, but the system worked.
雖然技術(shù)是落后的，但制度是有效的

adv.or （副詞） 或
backwards
To or toward the back or rear.
向后地：向或朝向后邊或后部地
With the back leading.
倒逆地：以后面的為領(lǐng)先地
In a reverse manner or order.
相反地：用相反的方式或次序
To, toward, or into the past.
回溯地：到、向或進入到過去
Toward a worse or less advanced condition.
退步地：向著不好或不太先進的狀況

<習(xí)慣用語>bend over backward 或
lean over backward
To make an effort greater than is required.
竭盡全力：做比所需的更大的努力
【引伸】
back.wardly
adv.（副詞）
back.wardness
n.（名詞）
The adverb may be spelledbackward or backwards, and the forms are interchangeable:
這個副詞可以被拼寫為backward 或者 backwards， 兩種詞形是可以互換的：
例句：
stepped backward;
向后踏步；

例句：
a mirror facing backwards.
朝后面的鏡子。

Onlybackward is an adjective:
只有backward 是形容詞：
例句：
a backward view.
后面的風(fēng)景