be busy with study还是be busy at study be busy with与be busy at的区别是什么?

be busy with study还是be busy at study be busy with与be busy at的区别是什么? BE busy with 还是 BE busy to be busy 什么 on还是of还是for还是with be busy with sth be busy with be busy with sth be busy with英译汉 he is always busy___ (work)是用be busy doing sth还是 be busy with sth 用be busy with 造句 be busy with的近义词? be busy with 后加名词,后面可以加动名词吗?比如说,i'm busy with doing my homework.还是只能说i'm busy doing my homework. be busy with与be busy doingD的区别 be busy with sth 与be busy doing sth be busy with和be busy for的区别 be busy with doing 与be busy doing 区别 be busy with sth 和 be busy dong be busy with sthI'm busy with swimming.I'm busy with going swimming.区别 be busy in 的用法?它和be busy doing, be busy with有什么区别?