■ birth

涉及分别的多人时，可以用复数。

• (the study) has been following several thousand twins since their births in 1994 and 1995.（这次调查）追踪了几千名双胞胎，从他们 1994 与 1995 年出生时起（参见 life, death 条）。

• posture
• potato
• poultry
• pour
• power
• power
• predate
• prefer
• pregnant
• prejudice
• premium
• prepare
• presence
• present
• presently
• president
• pressure
• prevent
• price
• prime minister
• prior to
• problem
• problem 与 question
• proceed
• productive