Question

Either you or the headmaster ___ the prizes to those gifted students at the meeting.

Answer 1

D
be
to
do
sth表示将要做某事，be
doing表示正在做。而原句意思应该是即将颁奖给学生。例句：I
don't
know
what
is
to
be
done
next.
不知下一步该怎么做。
用is，这是属于主谓一致原则中“就近一致”原则，适用于"or,
either...
or,
neither...nor,
not
only...
but
also"等句型，也就是说谓语要和后面的主语保持一致。
下面是几个例句：
You
or
Tom
is
going
on
business.
Neither
you
nor
I
am
wrong.
Not
only
the
students
but
also
the
teacher
wishes
for
a
holiday
希望能有所帮助:)

Answer 2

考查主谓一致。

由连词or,
either...
or...,
neither...nor...,
not only...but
also...等连接两个名词作主语时，谓语动词的数由邻近的名词或代词来决定，即跟headmaster保持一致，由此可以排除b和c；又因be
to
do
sth.表将来，因此答案为d。

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希望可以帮到你哦！望采纳
谢谢！o(∩_∩)o