题目

1.Jill and Katy _________________________with their class tomrrow
Aare going to swimming Bare going swimming C go to swimming Dgo swimming
2.They promised————————————the work in three days
Ato finishB finishingCfinishesDfinished
3.若b+c分之一=1.c+a分之一=1,求b分之ab+1

提问时间：2020-10-14

答案

A be going to do sth. 将来做某事  

A  promise to do sht. 承诺做某事

1

由b+1/c=1

得：b=1-1/c=(c-1)/c,则1/b=c/(c-1),
由c+1/a=1

得：1/a=1-c,则a=1/(1-c),
因此
b/(ab+1)

=a+1/b
=1/(1-c)+c/(c-1)
=1/(1-c)-c/(1-c)
=(1-c)/(1-c)
=1