began to后加什么？
begin to do 后面接的sth（某事），表示开始做某事;
begin to do sth里面的动作是突发的，不是习惯
The train began to pick up speed.
火车开始加速。
She began to explain her plan of action to the group.
她开始向小组讲解她的行动计划。
He began to question the ethics of his position.
他开始对他的立场是否符合道德准则提出质疑。
Slowly, an image began to appear on the screen.
屏幕上慢慢地出现了一幅图像。