call on 社交上的正式用语，指无目的、礼节性的短暂拜访，访问者与被访问者之间一般只有社交或公务关系。
see 常用词，含义广泛，既可指接受他人来访，又可指去访问他人。
visit 正式用词，强调出于工作需要的访问，也指亲戚朋友间的看望。
drop in 多指在计划之外或事先未打招呼的偶然、顺便访问。也可指参观。
参考例句
1. When I looked out of the window I saw her crossing the road. 我向窗外看时，看见她在过马路。
2. Here is what I see this month. 以下是我在这个月看到的事。
3. I wonder if you see all this. 我想知道你是否看到了这些。
英英解释
n.
1. the seat within a bishop's diocese where his cathedral is located
2. perceive by sight or have the power to perceive by sight
3. perceive (an idea or situation) mentally
4. perceive or be contemporaneous with
5. imagine; conceive of; see in one's mind
6. deem to be
7. get to know or become aware of, usually accidentally
8. see or watch
9. find out, learn, or determine with certainty, usually by making an inquiry or other effort
10. come together
11. be careful or certain to do something; make certain of something
12. go to see for professional or business reasons
13. go to see for a social visit
14. visit a place, as for entertainment
15. take charge of or deal with
16. receive as a specified guest
17. date regularly; have a steady relationship with
18. see and understand, have a good eye
19. deliberate or decide
20. observe as if with an eye
21. observe, check out, and look over carefully or inspect
22. go or live through
23. accompany or escort
24. match or meet
25. make sense of; assign a meaning to
