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The mystery stories of Sir Arthur Conan Doyle are famous all over the world.
The detective in his stories is called Sherlock Holmes.He solves mysteries in a most surprising way.Through it all,his assistant,Dr.Watson,watches with admiration（饮佩）.Watson then writes up the story of the mystery afterwards.
This is a useful story writing skill.Because Watson is not very clever,the story remains a mystery until the end.The readers can sometimes pick up some clues before he does！Then,to make Watson understand the mystery,Holmes has to explain it all,step by step.So we,the readers,get to see it step by step,too.Watson is almost as good a character in the story as Sherlock Holmes！
The very first time they met,Holmes greatly surprises Watson.When they are first introduced,Holmes says to Watson,"How do you do？I see you have been to Afghanistan."
Watson is too amazed by this to ask Holmes how he knows this.Watson has,indeed,been to Afghanistan.Later,he asks Holmes about it.Holmes explains that there is nothing magical about what he does.He gets to know it all by very,very careful observation.
Observation One Watson was introduced to Holmes as a doctor.Yet Holmes thought that the way he stood and walked made him seem like a soldier.So,this meant he was probably an army doctor.
Observation Two Watson's face was quite dark skinned.But his wrists were pale.So his dark face was probably sun burnt.This meant that he had been to a hot,sunny country.As he was a working doctor,this was not a holiday.He must have gone with the army.
Observation Three At the time,the British army had soldiers at bases in many parts of the world.So there were still a lot of places to choose from.However,Holmes saw that Watson looked very tired and he was always holding his left arm,as if it was painful.So,he had probably been with the army to a place where they were fighting.There was only one place where the British army was fighting at that time：Afghanistan.



Sir Arthur Conan Doyle ______ .

A. is a detective in mystery stories
B. is Sherlock Holmes' assistant
C. is a soldier in the British army
D. writes famous mystery stories

Dr.Watson watches Holmes with admiration because ______ .

A. Holmes solves mysteries in a most surprising way
B. Watson is not very clever
C. people always come to Holmes for help
D. the story of the mystery is written up afterwards

The writer most probably created the character,Dr.Watson,to ______ .

A. give Holmes help when solving mysteries
B. show Holmes' careful observation
C. help readers pick up some clues about the mystery
D. get readers to see the mystery step by step

The first time they meet, ______ .

A. Holmes explains how he knows Watson has been to Afghanistan
B. Holmes surprises Watson by telling that he has been to Afghanistan
C. Watson tells Holmes he has been to Afghanistan
D. Watson asks Holmes how he knows he has been to Afghanistan

In"Observation Two"，the underlined word sun burnt probably means ______ .

A. caused by illness
B. made brown by sun
C. painted by make-up
D. given by his mother

The passage tells us that Watson went to Afghanistan to ______ .

A. fight the enemy for the country
B. have a holiday with his friends
C. work as an army doctor
D. stay away from the cold,rainy weather of London

From the passage we know that the British army ______ at that time.

A. only had soldiers in Afghanistan
B. had many army doctors at bases in only one part of the world
C. was fighting with several countries
D. was fighting with Afghanistan