下列关于 MySQL基本表和视图的描述中，正确的是 ______。
A、对基本表和视图的操作完全相同D
暂无解析
Ithinkthe______(four)lessonisthemostdifficultinthisbook.
()It'snineo'clock.Imust______.
阅读理解，根据短文内容判断正(T)误(F)。
It'sSundaymorning.ThestudentsofClass3aregivingtheirclassroomagoodcleaning.
MissHuang,theirteacher,isworkingwiththem.Thechildrenarebusy.Somearecarryingwater;
somearecleaningthewindows;othersaresweepingthefloor.ZhangHuaisputtingupamaponthe
wall.ItisamapofChina.WangFeiandWeiQingaremendingsomebrokenchairs.Thechildrenare.
listeningtotheradiowhiletheyareworking.Theclassroomlooksniceandbrightafterthecleaning.
Thechildrenareveryhappy.Theygohomeforlunchatnoon.
()1.ThechildrenareplayingintheirclassroomonSundaymorning.
()2.MissHuang,theirmother,isworkingwiththem.
()3.ThereisamapofChinaonthewall.
()4.Twoofthemarerepairingthebrokenchairs.
()5.Theyaresingingwhiletheyareworking.
Thereare_____studentsinourclass.Thatis19boysand21girls。
如图所示，小车放在光滑的水平面上，将系绳小球拉开到一定角度，然后同时放开小球和小车，那么在以后的过程中()
