Exactly______ the potato was introduced into Europe is uncertain, but it was probably around 1565.
#30010
A
whether
B
why
C
when
D
how
推荐题目
Be quick, _____ we’ll miss the beginning of the fireworks display in the park.
#31590
A
so
B
or
C
because
D
though
His parents were teachers in that school, _______ lost their lives in order to save their students in the earthquake.
#32666
A
none of them
B
both of them
C
none of whom
D
both of whom
Here is a survey about hopes and dreams ______ thousands of students took part.
#30957
A
at which
B
in which
C
with which
D
about which
You should be careful of such a person flatters you in your presence and speaks ill of you in behind.
#33297
A
who
B
that
C
as
D
which
This summer North China was attacked by such a terrible heat few people has ever experienced before.
#30617
A
that
B
and it was
C
which
D
as