There are eight tips in Dr.Roger's lecture on sleep, and one of them is: to bed early unless you think it is necessary.
He asked us to him ______ carrying through their plan.
Only after my friend came ___________________________.
While ________ to foreigners,you must try your best to make yourself ________.
The computer system _____ suddenly while he was searching for information on the Internet.
about the journey, I was unsettled for the first few days.