assist sb to do sth中to可以去掉么?

assist sb to do sth中to可以去掉么? assist sb.to do sth.和assist sb.in doing sth.什么时候用assist sb.to do sth.什么时候用assist sb.in doing sth.最好能帮忙举个例子说明. 关于assist的一些词组的区别assist sb.with sth.assist sb.to do sth.assist sb.in doing sth.这三个词组的意思都是帮助某人做某事,它们有区别吗?区别在哪? assist sb in doing sth中in可否省略? 英语语法中,need sb sth是need sb to do 还是need sb do /doing sth? do sb.to do sth. want sb to do sth 和 tell sb to dowant sb to do sth 和 tell sb to do sth分别在句子中做什么成分? 使役动词中make,let,have sb.do sth.还是sb.to do sth. Help sb to do sth中to什么时候省略?举例. sb.happen to do sth. invite sb to do sth teach sb.to do sth. keep sb to do sth told sb.to do sth. get sb.to do sth live sb to do sth ask sb to do sth wish sb to do sth