คำตอบ
I will have ... by ...
Later
At some time
I am/ have (...ed)
I will have been in Japan for 18 years this December.
Will have ...ed is used to explain a context and is not usually used by itself as context.
I will have turned 47 next month.
Without further context this is not natural.
I am going to be 47.
How long have you been a teacher?
I will have taught for 17 years this September.
This means that 17 years will have passed soon but at the moment, it is only 16 years and some months.
Will have done ... is often used when the future date is important in telling how long something has been happening or where one will be in the future.
たくさんありがとうございます！
I'll have love math after this next lesson.
This is a clumsy phrase and is not really used since you don't really know if you will love it in the future.
She will have understood the math problem by the time we meet tomorrow. She is now looking into it.
Oops. I will have loved math after ....
เมื่อดูคำถามนี้แล้ว
ก็จะเจอคำถามเหล่านี้ด้วย😉
สมุดโน้ตแนะนำ
総合英語be まとめ（１）
【総合英語フォレスト】まとめ（４）分詞／比較
【総合英語フォレスト】まとめ（３）態／不定詞／動名詞
ありがとうございます！