When were they there?回答是什么?（回答加中文）!谢谢〜

When they were There were as many serious problems when cars were parked as when they were traveling at 90 m/h THEY WERE THERE怎么样 They were working when I got there.（对画线部分提问）对were working提问___________ ___________ they __________ when I got there? When were they there?为什么不说“When were they at there?”句子是新概念英语的,字典上说there adv.在那里 n.那里本句中there在句子是名词吗?为什么不用When were they at there?When were they there?直接翻译的话 oh when they were young There was once ___ time ___ they were good friends 为什么填a,when when I got to the park,they were playing ( )there 这里填happy的什么形式 they were not having a meeting when l was there 改被动 when i got there,they were all at table的同义句 When were they there?回答是什么?（回答加中文）!谢谢〜 when they --the villige,they found the two girls were not there Areturned back to B returned to there gave one of the soldiersand when they begin questioning youland on which they wereflies were buzzing along the walls after they were born 和 when they were born What ___ they ___ when you got there?A.have,done B.were,doing C.did,he D.would,to Most human beings are as good as they are because some unsung teacher were there when needed They __flowers when I got there.Awatered Bwere wateringcare wateringA.watered B.were watering C.are watering Why? Most human beings are as good as they are because unsung teachers were there when needed.翻译成汉语