:a verb tense that is used to refer to an action that will be completed by a specified time in the future将来完成时（指将来某个时间将要完成的动作）
The future perfect in English is formed with “will have” and “shall have,” as in “They will have left by the time we arrive.”英语中的将来完成时由will have和shall have构成，如They will have left by the time we arrive。