before bottom center
下死点前在下止点前
before top dead center
在上死点前在上止点前
after bottom dead center
下死点后在下止点后
So the exhaust valve opens before BDC and closes after TDC.
因此排气门在下止点之前打开，在上止点之后关闭。
The Bore is the diameter of the cylinder. The stroke is the distance the piston travels from BDC (Bottom dead center) to TDC(top dead center). The Bore is always mentioned first.
内径指的是气缸的直径;行程是活塞从下止点运行到上止点的距离。表述时,内径总是写在前面。
Fold the shoulder seam downwards. Cut from point C around the front neckpoint to point B. cut down around the armhole. Stop before reaching the underarm point.
折叠肩的缝线。从C点开始剪,沿着前颈点到B点。沿着袖窿往上剪,到达腋下点前停止。
after top center
上死点后在上止点后
Arthroscopic technique of figure-of-eight suture fixation for avulsion fracture of anterior cruciate ligament in adults:report of 24 cases
关节镜下“8字”缝线法治疗成人前交叉韧带下止点撕脱骨折24例
Passengers must board the ship by 6 p.m.
旅客必须在下午六点钟以前上船。
Please renew offer until March 23, 4 p.m.
请在3月23号下午四点前重新报价。
Marshal your arguments before debating.
在辩论前,整理一下你的论点。
Not if you leave before 00 p.m.
如果您在下午5点以前离开就不用。
I'll finish working at 5:30 and get home by 6 o'clock.
我将在五点三十分下班，六点钟以前回到家。
So number one: remember to let the racquet fall (at least one foot below the contact point) before swinging forward.
因此第一：记得在向前挥拍之前让网拍降下（在接触点下面至少一呎）。
The reporter 's deadline is 8 p.m. for the morning edition
记者给上午版发稿的截止时间是(前一天的)下午八点
The reporter's deadline was 8 P.M. for the morning edition.
记者给上午版发稿的截止时间是(前一天的)下午八点。
Arthroscopic reduction and fixation of anterior cruciate ligament(ACL) avulsion fracture from the tibia spine with suture
关节镜下丝线内固定治疗前交叉韧带胫骨棘止点撕脱骨折
It's snowing here, but I think I can get there before 12 o'clock."
外面正在下雪，大概在12点之前我能赶到。