1.
a).The boat was under the bridge.
b).The boat was below the bridge.
2.
a).I am quite at fault.
b).You aremuch in fault.
c).He is faithful to a fault.
3.
a).He spoke nothing on purpose.
b).He spoke nothing to the purpose.
c).He spoke nothing to no purpose.
4.
a).He knows German, to say nothing of English.
b).He knows German, not to say English.
5.
a)Have you ever seen such a picture?
b)Did you ever see such a picture?

1.
a).船在桥下.
b).船在桥的下流方.
2.
a).我十分迷惑.(at fault = at a loss, in a puzzled)
b).你咎有应得.(in fault = guilty, to blame)
c).他非常忠实.( to a fault = excessively, too (much))
3.
a).他故意什么都没说.(on purpose故意)
b).他说的一点也不得要领.(to the purpose中肯)
c).他所说的无不生效.(to no purpose无效)
4.
a).他懂德语,英语自不待言.
b).姑且不说英语,德语他也懂得.
5.
a).你看到过这样的画没有?
b).你恐怕没有见过这样的画吧?