【单选题】由与非门构成的RC环形多谐振荡器如图所示,当n=101时,振荡周期为10.1μs,则每个与非门的平均传输延迟时间t dp 为( )。
【单选题】Don't hesitate to ______ us if he doesn't ______ in time. [ ]
【单选题】Don't forget to _____ the lights after school. [ ]
【单选题】Don't forget _____ the computer when you don't use it. [ ]
【简答题】B3U3 passge 1 Turn to page , and choose the best anwer to each question you hear.
【单选题】—Don't forget ___ the tap when you don't use it. —No, I won't. [ ]
【单选题】Don't forget _____ the tap when you don't use it. [ ]
【简答题】B3U1 Long conversation Turn to page 19,and choose the best anwer to each question you hear.
【单选题】He told his brother _____ off the radio . [ ]