潜水是埋藏在第一个隔水层以上的地下水。读下面四幅水体相互补给示意图,回答以下问题。有关图中补给关系的说法,正确的是
关于陆地水体的相互联系的分析,不正确的是
Rules are helpful to us,______ we have to follow them.( )
A.soB.butC.orD.because
Tim is going to give his father a surprise ______ Father's Day.( )
A.inB.atC.onD.by
Ladies and gentlemen,attention please!I have ______ important to tell you.( )
A.nothingB.somethingC.everythingD.anything
I like hiking in the forest because the air is pretty ______.( )
A.freeB.dirtyC.pollutedD.fresh
﹣______ do you usually share happiness with?
﹣My parents and my best friend.( )
A.WhoB.WhoseC.WhatD.How