at the desk固定搭配?一定用at?

at the desk固定搭配?一定用at? “A chair is at the desk. A number of audience were present in the registration center in the morning,the number of whom wasbe present at是固定搭配吗?这里用“be present in 是否正确?到底是不是固定搭配哟，老师经常说be present at ,be absent from啊 There is a wallet __ （lie）on the ground.为毛用lying啊?如果固定搭配那固定搭配怎么推出来的呢 Look at the picture!A desk is itLook at the picture!A desk is it在图片里还是在图片上,用in还是on the student is sitting at his desk 为什么用at? 为什么 tell the truth,用the?而 tell a lie,tell a story,用a?固定搭配吗? We can't see who will laugh ( )A.at the endB.in the endC.by the endD.to the end顺便问下,是固定搭配,还是随情景变化搭配就不同? The football fans cheered their team _____ the entrance _____ the field.A. at; on B. in; at C. at; to D. on; at这题答案选择C,我知道前面是固定团搭配,在入口处.可是后面为什么用to? 24.Japan is ________ the east of China.　　A.inB.toC.onD.at选什么?选的这个是固定搭配吗? sign at the first desk While two detectives were keeping guard at the door请问这里的guard at the door是固定搭配吗? on a visit有没有on the visit这种说法?为什么要用a?是固定词组搭配还是? take exams______ all subjects.A.at B.on C.by D.in是固定搭配么？ at desk/table,at the chair/desk的区别 at the desk和 at desk的区别是 表特定时间的介词___the scheduled afternoon,I introduced the activity to my classmates.A.At B.On C.InWhich and Why?At the afternoon?不是固定搭配吧In the afternoon 才是固定搭配但这里是一个特定的时间啊....... at the desk和 near the desk区别是什么