关于英语动词加介词的问题例如：I don't believe in everything the Bible says.不及物动词后面要+介词后才能+宾语很多动词既是及物又是不及物,例如：believeI don't believe everything the Bible says.这2句话有啥区别啊

两者不同:
(1) I don't believe everything the Bible says.(相信...)
(a) I believe his story. 相信 ; I believe you. 信任
(2) I don't believe in everything the Bible says.(信仰，相信......的存在/价值)
(a) Do you believe in ghosts?;
(b) He believes in capital punishment
(c) If you believe in yourself you can succeed.
(d) He believed in marital fidelity.

我是最快回答的哟：
在这2句话中都能用都能用.
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believe,believe in
这一对词语都表示“相信不疑”的意思,但词意有细微的区别.
Believe表示“相信”、“信以为真”（to accept as true）之意,它是及物动词,其后直接跟宾语.例：
Do you believe his reports?你相信他的报告吗?
I could hardly believe my eyes．我几乎不能相信自己的眼睛.
In ancient times it was believed that the earth was flat．古时候,人们认为地球是扁平的.
Believe in则表示“信仰”、“信任”（to have faith in somebody or something）之意.其后的常用搭配语为：有关宗教、理论、原则、概念及可信任之人,如：a religion、ghosts、 fairies、 a theory、 a friend等词；例中的believe为不及物动词.如：
We do not believe in ghosts．我们不信鬼神.
He believes in getting plenty of exercise．他相信多锻炼身体就会有好处.
In the days of the French Revolution,people believed in liberty,equality and fraternity．
法国大革命时代的人们信奉*、平等及博爱.
现在试比较下列两语的不同涵义：
I believe him．（=I believe what he says）我相信他（的话）.
I believe in him．（=I trust him ）我相信他是一个可以信得过的人.（即：我信任他）
在英美人的谈话中,经常可以听到这么一句口头禅——Believe me：这是一个用以表示希望对方相信自己谈话的口头语,它相当于I bet或 Take my word for it.例：
Believe me,you will get well very soon．你一定会很快就恢复健康的.
Believe me 可以根据不同的场合,译作“真的”、“我不骗你”、“一定会”或“请相信”.