单项选择题 If either party wants to renew the contract, it should submit a written notice to the other party three months prior to the expiration of the contract.

单项选择题 For your safety, the electrical appliance can only operate when it has been correctly mounted on a dry and cool base.

单项选择题 Not only does asking questions at a meeting involve you in discussions, it is also a good way to demonstrate your professional knowledge.