【判断题】DNA的三级结构是指DNA双螺旋进一步扭曲盘绕所形成的特定空间结构。超螺旋结构是DNA三级结构的主要形式,可分为正超螺旋与负超螺旋两大类,它们在特殊情况下可以相互转变。
【单选题】What's the"blessing of email?
A.
With email, you only deal with its message on your own time.
B.
You can't avoid all the hellos, goodbyes and other unnecessary chit-chat.
C.
It's an interactive conversation.
D.
Email isn't designed for convenience.
【单选题】It was with great joy _____ he received the news that his lost daughter had been found. [ ]
【简答题】“资料大师——《工程资料管理系统》”是一款适合各省市具体情况的软件系统,其中含有工程施工验收全过程所需的各种类别的技术资料,如工程建设前期资料,监理管理资料、施工过程中的()资料、()资料、国家及各省市当地规定的验收标准和质量验收规范和规程等。该软件系统还可以对输入的数据进行()处理。
【简答题】It’s great to receive your email. Now I’d like to tell you something took place in my school yesterday. In the afternoon, we 小题1: _ h______ a growing-up ceremony for our coming 18-year-old ...
【单选题】The chances of the physical sciences being subject to great changes are the biggest because
A.
contradictory theories keep emerging all the time
B.
new information is constantly coming in______.
C.
our knowledge of it is highly insecure
D.
only a very small sample of it has been observed