TCP协议在两台计算机之间提供可靠的()。

________ with the size of the whole earth, the highest mountains do not seem high at all.

It is useful to science _______ the earth as an object in space.

在Internet术语中，Internet网关是指()。

We must ______ that the experiment is controlled as rigidly as possible.

Be careful, _______ you'll fall down.

_______ the movie I would have finished my paper last Sunday.

The boy ran out of the classroom without the teacher's _______.

I'm sorry I forgot to write; I had so much else ________ my mind.

I don't know how we can make ________ on the timetable for any more courses.