sign

1.I have signed my name to the cheque和They will be requested to sign their names to the petition等句子里的to不可改作in或on。

2.I have signed the cheque和They will be requested to sign the petition等句子里的signed和sign后面不可加上in，on或to。

3.He signed to her to enter the room（他做手势叫她走进这房间）等句子里的to可以省去，但通常不省去。

4.signs后面可以接以that引导的从句。例如：There were signs that the minister would resign.