怎么从动词的意思上辨别它是及物还是不及物?总不至于背单词时要一起记住那个vt,vi吧,应该可以从意思上区别吧?

本身意思完整的动词称为不及物动词，后面不跟宾语。表示动作由主语传到另一人或物的称为及物动词，动作所传及的这个人或物称为宾语。
参考资料：《英语语法大全》

A 有些动词只是及物动词; 它们不可以单独用，后面必须跟宾语。
{ False: They always want after lunch.
Right: They always want a cup of tea after lunch.
{ False: He is sending now.
Right: He is sending a letter now.
B 有些动词只是不及物动词；它们可以单独用，如果后面想接宾语，动词后面必须加上介词。
{ Right: He is looking around.
False: He is looking me.
Right: He is looking at me.
{ Right: He is listening carefully.
False: He is listening the teacher carefully.
Right: He is listening to the teacher carefully.
C 有些动词既是及物动词，又是不及物动词; 但是有时候词义会改变。
{ The customer is asking loudly.
The customer is asking for you now.
The customer is asking a question now.
{ If you work hard, you will succeed.
If you work hard, you will succeed in passing the exam (same meaning).
If you work hard, you will succeed John as the manager of this company (different meaning).

个人感觉是你理解一个单词,想一想他后面能不能跟着对象,这应该会比较好记.比如说“kick”,是“踢”的意思,如果你会想到“踢球”这个词,你就可以判定它是“及物动词”类似的还有“build"建造(楼房) ”play“玩（游戏...