She sat at her desk, with her eyes__________on the book, ________in its plot[ ]

Though _______ not to,the girl let out the secret [ ]

Is the post office _______ our school? –No, it’s only about 2 kilometers .You can walk there.

You may ______ your teachers for help when you have problems.

This machine is very easy ________. Anybody can learn to use it in a few minutes.[ ]