Monday， January 21^st

   I'm a virus （病毒） for the common cold． It has been a long time since I infected（感染） humans last time． Today I tried to infect a boy in a primary school all day． His name is Sam． I waited on his desktop， and when he touched the desk I jumped on his finger． Unluckily， Sam didn't touch his eyes， mouth or nose．Then， right after class， he washed his hands．Now I'm full of soap and sitting in a sink!

Tuesday， January 22^nd

    This morning I jumped into the nose of Sam's best friend， Bill．Unluckily，the mucus （粘液）in his nose caught me． I thought it was over for me，when suddenly Bill sneezed while he was talking to Sam． I knew that would send me right into Sam 's face! However， Sam quickly gave Bill a tissue， and Bill sneered into that instead! Infecting people is harder than I imagined．

Wednesday， January 23^rd

    I'm feeling very unhappy today．Some scientists caught my friend Harry and put him under a microscope． Harry is a flu virus and he's a dangerous little guy．Besides，Sam ate all his vegetables today．He's exercising， and he's getting eight hours of sleep every night． His body is too strong for me!

Thursday， January 24^th

    I tried to infect Sam again today， but he washed his hands five times and never touched his face! He also gave tissues to every student in his class who was sneezing． It's impossible to give him a cold! So I have to give up and I'm moving to another school．

（1）According to the passage， life of the virus for the common cold could be 　　．

A． easy

B． lucky

C． dangerous

D． difficult

（2）The underlined word "his" in the passage refers to 　　．

A． Sam's

B． Bill's

C． Harry's

D． Bill's friend's

（3）The writer is trying to tell us that 　　．

A． viruses feel happy， sad and angry just as people do

B． we should be friendly when other people around you are sick

C． it's important to protect your own body against viruses

D． many viruses around us like to infect boys in primary schools

（4）The best title for the passage above might be "　　"．

A． Danger of a Virus

B． Habit of a Virus

C． Diary of a Virus

D． Letter of a Virus