what is she?She __________ a visitor around the city.为什么空格里要

shows 是一般现在时,而is showing是现在进行时.在这里,如果用一般现在时,意思就是她经常做这个事,是一种经常性,或习惯性的动作.
①一般现在时的用法

1) 经常性或习惯性的动作,常与表示频腮度的时间状语连用.
时间状语： every…, sometimes, at…, on Sunday
I leave home for school at 7 every morning.
2) 客观真理,客观存在,科学事实.
The earth moves around the sun.
Shanghai lies in the east of China.
3) 表示格言或警句中.
Pride goes before a fall. 骄者必败.
注意：此用法如果出现在宾语从句中,即使主句是过去时,从句谓语也要用一般现在时.
例：Columbus proved that the earth is round..
4) 现在时刻的状态、能力、性格、个性.
I don't want so much.
Ann Wang writes good English but does not speak well.
比较：Now I put the sugar in the cup.
I am doing my homework now.
第一句用一般现在时,用于操作演示或指导说明的示范性动作,表示言行的瞬间动作.再如：Now watch me, I switch on the current and stand back. 第二句中的now是进行时的标志,表示正在进行的动作的客观状况,所以后句用一般现在时.

②现在进行时

现在进行时的基本用法：
a. 表示现在( 指说话人说话时) 正在发生的事情.
We are waiting for you.
b. 习惯进行：表示长期的或重复性的动作,说话时动作未必正在进行.
Mr. Green is writing another novel.
(说话时并未在写,只处于写作的状态.)
She is learning piano under Mr. Smith.
c. 表示渐变的动词有：get, grow, become, turn, run, go, begin等.
The leaves are turning red.
It's getting warmer and warmer.
d. 与always, constantly, forever 等词连用,表示反复发生的动作或持续存在的状态,往往带有说话人的主观色彩.
You are always changing your mind.
典型例题
My dictionary ___, I have looked for it everywhere but still___ it.
A. has lost, don't find B. is missing, don't find C. has lost, haven't found D. is missing, haven't found.
答案D. 前句是一个仍在持续的状态,应用进行时,由于没有找到,其影响仍然存在,应用完成时,瞬间动词用于否定式时可用于完成时.

要用现在进行时

错误,应是what is HER?
她正在为一个游客导游整个城市

问题错误!
正确的为:what is she doing?
这么一来,答案当然是is showing.问题问的是现在进行时,所以回答也要用现在进行时.
如果问题问:what does she do?
则回答必定是:she shows a visitor around the city.