某细胞中染色体的组成是22条常染色体+X染色体，该细胞可能是人体的[ ] A．卵

     Have you heard of the term "etiquette" and do you know that etiquette is not only a useful
word __1__ very useful to understand? Etiquette is not the same in every culture __2__ in every
situation. For example, standing very close to the person you are talking with is quite common in
some Asian countries. However, if you do this in Europe, some __3__ people might feel __4__.
Even in China, we all know that etiquette is not the same in all situations. Perhaps we think that
talking loudly in our own homes is fine, but there are other places where talking loudly is __5__.
For example, most people would agree that talking loudly in a library, a museum, or a movie theater
is __6__. Even if you are with your friends, it is better to keep your voice __7__in public places.
In fact, we should also __8__ not to cough or sneeze loudly in public.
     If we see someone __9__ the rules of etiquette, we may politely give them some suggestions.
Perhaps one of the most polite ways _10__ ask someone, Would you mind doing this or would
you mind not doing that. For example, if someone cuts _11__ you in a line, you could ask them,
Sorry, would you mind _12__ the line? If someone is smoking on the busm, you could ask, Excuse
me, could you please _13__ that cigarette? People don't usually like _14__ , so we have to becareful
how we do this.
     Although rules of etiquette can often be different, some rules are the same almost everywhere
in the world! For example, _15__ is almost never allowed. If you see someone you know doing
this, you can ask them, Would you mind picking it up?