【单选题】【消耗次数：1】
I found hard to concentrate.
①
this
②
that
③
it
④
what
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相关题目
【单选题】
He found it hard to ( ) his studies in such a noisy environment.
①
devote to
②
dwell on
③
concentrate on
④
depend on
【单选题】
They are working hard to____ what they have lost.
①
make out for
②
keep up with
③
catch up with
④
make up for
【单选题】
I found the article while I was （ ） some old magazines.
①
browsing through
②
looking into
③
staring at
④
watching out
【单选题】
I found the book you recommended in the library, ______ is missing.
①
the front cover of which
②
the front cover of that
③
that front cover
④
of what front cover
【单选题】
What _________ if I drink this ?
①
happens
②
is happening
③
will happen
④
is happened
【简答题】
I found it important __________ learn.[填空1]
【单选题】
I found a ___________ young man lying on the ground.
①
wound
②
wounding
③
wounded
④
wounds
随机题目
【单选题】
一个n位字长的采样，其样本值映射到（ ）之内。
①
<img class="kfformula" src="20200528/1590626423354468.png" data-latex="0\sim {2}^{n}" width="94" height="39"/>
②
<img class="kfformula" src="20200528/1590626423162963.png" data-latex="0\sim {2}^{n}+1" width="131" height="43"/>
③
<img class="kfformula" src="20200528/1590626423471895.png" data-latex="{2}^{n}" width="62" height="40"/>
④
<img class="kfformula" src="20200528/1590626423983895.png" data-latex="0\sim {2}^{n}-1" width="133" height="42"/>