VOA慢速英语:Japan Plans to Increase Coast Guard Forces in East China Sea(翻译)

substantially – adv. by a very large amount

capability – n. ability or power to do something

patrol –n. a group of people, vehicles, etc., that go through an area to make sure that it is safe​

vessel – n. a ship or large boat

upgrade – n. when a thing is replaced by something newer, better, etc.