To menstruate is to have a period: blood leaves the body as part of the monthly cycle. It is the verb.

To menstruate來月經（menstruate） is to have a period就是有生理期：blood leaves the body血液離開身體 as part of the monthly cycle是每月週期的一部分。It is the verb這是動詞。

A person menstruates; they started to menstruate at thirteen; some people menstruate heavily, some lightly, some hardly at all. Doctors and textbooks use it; everyday talk is “I got my period” or “I’m on my period.” “She is menstruating” is clear, not unkind — just stiff.

A person menstruates一個人來月經；they started to menstruate at thirteen她十三歲開始來月經；some people menstruate heavily, some lightly, some hardly at all有些人量多，有些人量少，有些人幾乎沒什麼量。Doctors and textbooks use it醫生和教科書會用這個字；everyday talk is 'I got my period' or 'I'm on my period'日常口語會說「我來月經了」或「我在生理期」。'She is menstruating' is clear, not unkind「她正在來月經」這句話清楚，並不帶惡意——just stiff只是有點生硬。

The word is built from an older word menstruum plus -ate, which turns it into a verb. The “have a period” sense probably comes backwards from menstruation; scholars are not sure. There is also an old describing use of menstruate, but you will almost never meet it now. Use the verb.

The word is built from an older word menstruum這個字是從一個更古老的字menstruum而來，plus -ate加上-ate，which turns it into a verb讓它變成動詞。The 'have a period' sense「來月經」這個意思 probably comes backwards from menstruation可能是從menstruation反過來造出來的；scholars are not sure學者也不確定。There is also an old describing use of menstruatemenstruate也有一個古老的形容詞用法，but you will almost never meet it now但你現在幾乎不會遇到。Use the verb用動詞就對了。

Though actually, people sometimes stretch it: “She hasn’t menstruated in months” can be a body fact (stress, sport, pregnancy, age), not a moral one. The word names what the body is doing.

Though actually不過其實，people sometimes stretch it人有時會把它用得更寬鬆：'She hasn't menstruated in months'「她好幾個月沒來月經了」，can be a body fact可能只是身體上的事實（stress, sport, pregnancy, age壓力、運動、懷孕、年紀），not a moral one而不是道德上的問題。The word names這個字指的是 what the body is doing身體正在做的事。

Schoolbooks still say “girls menstruate” as if that were the whole story. Most people who menstruate are girls and women, but not all of them, all the time.

Schoolbooks still say學校課本還是會說 'girls menstruate'「女生會來月經」，as if that were the whole story好像這就是全部的事實。Most people who menstruate大部分會來月經的人 are girls and women是女生和女性，but not all of them, all the time但不是每個人、每次都是這樣。