Have to be at the middle/front/top of

Have to be at the middle/front/top of i have to be on top of the matter? 用in front of,below,at the top,behind,at the bot-tom,above 形容 There _______ a tower at the top of the hill.A used to have 英语翻译1,be ready to do 2,at the top of 3,in the center of 4,at 选用合适词组填空.at the top of,make efforts,be connected with,up to, at the front of 帮忙翻译一下a middle sized plate placed in front of the person at at the top of the on the top of,at the top of,on top of ,at top of, 用 in front of 和 behind和above和at the top和at the bottom,造句5个 at the top of every