■ bow and arrow

“弓箭”如果理解为一种武器的整体，作为主语时动词用单数。

• The bow and arrow was invented at that time.弓箭是那个时候发明的。

• dark
• dark eye
• dark eye 与 black eye
• darkness
• dark 与 darkness
• date
• dead
• dead
• dead 与 die
• deal
• deal with
• dear
• death
• debate
• decadent
• deceive
• decide
• declare
• decline
• dedicate
• deep down
• defense
• defy
• deny
• dependable