the bus is coming的coming为什么加ing?

the bus is coming的coming为什么加ing? The bus is coming () The bus is coming The bus is coming的同义句 come的用法谁能帮我总结一下?Here comes the bus.为什么不是is coming?那I coming有 thank you all for coming的coming为什么要加ing The shool bus is coming.的同义句是什么 The bus is coming.let's( ). Be _____!The bus is coming. the bus is coming ____us .be careful H up,the bus is coming Be ___!The bus is coming.