1a-b. か (ka)
2. かな (kana)
3. かしら (kashira)
4. の (no)
5. って (tte)
Indicates a question at the end of a sentence. Its tone has the politeness expected in everyday conversation with strangers or social superiors, in contrast to the casualness indicated by particles 2, 5.
Yamamoto: How is work going these days?
Takeshita: Not as smoothly as before.
Kyoko: Who won yesterday’s game?
Naomi: The A team, of course.
1b. か (ka)
Indicating a question, doubt, or uncertainty in mid-sentence.
Maybe I’ve caught a cold—I’ve had a sore throat today since morning.
I don’t know how many people are coming to tomorrow’s gathering.
Typically used by men, indicates a tentative question or uncertainty at the end of a sentence. The feminine equivalent is かしら (3), both in function and in casualness of tone. English equivalent: “I wonder.”
Section chief: I wonder if everyone knows about the emergency meeting starting this afternoon.
Subsection chief: Don’t worry about it. An email has been sent out.
Husband: I’m going golfing tomorrow. I wonder if Takada won’t go too.
Wife: Why not call and find out?
Typically used by women, indicating a tentative question or uncertainty at the end of a sentence. The masculine equivalent is かな (2), both in function and in casualness of tone.
Wife: I wonder what happened? I put it in my purse, but the key is gone.
Husband: Don’t worry. It’s there on the table.
Satomi: I wonder how good that new restaurant is?
Mie: It’s pretty good. Yesterday I went with Yuri to try it out.
4. の (no)
Spoken with rising intonation, indicates a question at the end of the sentence. Equivalent in function to か (1a) but provides a softer, more casual tone.
Mother: Have you already eaten?
Son: I haven’t finished yet. / I’m still eating.
Harumi: Where are you going?
Kumiko: I’m going out for a cup of tea. Why don’t you come along?
With a rising intonation, indicates a question at the end of a sentence, asking if what one has heard is true. Typical of the spoken language and most often heard between friends or family. Often found in the form of だって (datte), but can also follow a verb（食べるって taberu tte). Without the rising intonation, the question becomes a statement (as in Tomiko’s response in the second sentence below), meaning “I hear that….” English equivalent: “Is it true (as I have heard) that…?”
Yuka: Is it true there’s a French test tomorrow?
Tomiko: That’s what I hear. Ugh!
Takayarna: The department head’s already gone?
Kondo: That’s correct.