— Father, you promised!

—Well,____．But it was you who didn't keep your word first．

so was I 

so did I 

so I was 

so I did

考查部分倒装“So + be/情态动词/助动词 + 主语”与表强调的“So + 主语 + be/情态动词/助动词”区别。根据语境“you promised（你许诺过）”和答语“But it was …”可知爸爸回答“我的确许诺过”，且promised是过去时，所以表强调要用助动词did,故选D。句意：——爸爸，你许诺过。——好啦，我的确许诺过。但是是你先没有遵守诺言。

It was last night ________ I saw the comet.

the time

when

that

which

强调句的结构是：It＋be＋强调部分＋that(who)＋主谓句。强调句的连词只有两个，that和who。当强调的部分是人，且为句子的主语时，才用“who”，其余用that。因此选C。

Great amounts of water            poured into the river from the factories two years ago.

was

were

has been

have been

考查时态和主谓一致。句意：两年前，工厂将大量废水排入河中。根据two years ago 可知，句子使用一般过去时。....amounts of修饰不可数名词作主语时，谓语动词用复数形式，即谓语动词与amounts保持数的一致。故选B项。

The most important promises we must keep are          we make to ourselves.

ones

those

these

them

考查代词。句意：我们必须遵守的最重要的承诺就是我们对自己做出的承诺。A. ones泛指上文提到的可数名词复数；B. those特指上文提到的可数名词复数；C. these这些；D.them他们。分析句子可知，为we must 是定语从句，修饰The most important promises，是句子的主语；be动词后缺少表演，we make to ourselves是定语从句，修饰空格处。根据句意，此处指上文提到的promises,由定语从句修饰表示特指，故用 those。故选B项。