1、准时地
... on the spot当场,当即;在现场 on the stroke准时地 on the table(摆)在桌面上,公开地 ...
2、准点地
... on the run 奔跑着；奔逃着 on the stroke 准点地 on the whole 大体上；基本上 ...
on the contraryterfly stroke蝶泳
dolphin on the contraryterfly stroke海豚式蝶泳
on the stroke of midnight零时零分