The summations of forces in this and that directions must be zero.在这个和那个方向上的合力必定为零.Summations are almost invariably indicated ellipses instead of the more prevalent sigma notation.在表示“连加”的式子中,几乎一成不变地使用省略号来代替更为流行的“∑”符号....
Rain water was once considered to be good for the complexion.雨水曾一度被认为可以滋养皮肤。Oh great! That'll be good for Fergus.哦，太棒了！那将对弗格斯很有利。They argued all the time and thought it couldn't be good for the baby.他们一直在争论，认为这...
他的车遭遇拦劫，随后他被4名持枪歹徒劫持。His car was held up and he was abducted by four gunmen.他们拦劫了一辆的士,向电厂开去.They car jack a taxi and head to the power plant.这些带面具的人拦劫了那个职员,还把发薪薄带走了.The masked me help up the clerk and made away with the ...