how can I say "what about...?" in Japanese?


I was writing to my japanese friends, and I got some doubts. Hope it wasn't
asked here before.

How can I express "what about ..." in Japanese? Particularly:

> What about having some breaks?  
>  What about doing it on Mondays and Tuesdays?  
>  What do you think about this sweater?  
>  What do you think if we go tomorrow?  
>  How about openning the windows?  
>  What if we move this chair to another place?  
>  ...

I was thinking of:

> どうですか。  
>  いかがですか。  
>  よろしいですか。

Is the following correct?

> 月曜日と火曜日するのはどうですか。




You really have several choices depending on the exact meaning of the
question. If the question is making a suggestion for the listener to respond
with an answer, then `～（よ）うか` ("Shall we ～?") as mentioned, or just `～は？` if
the action has already been established.

>   * 日曜日にしようか？
>   * う～ん、日曜日はムリ。
>   * ほんじゃぁ、月曜日は？
>

If you're trying to give advice/suggestion/weak command to the listener in the
form of a "How about doing ～?" question, then `～たら（どう（ですか））？` is what you
want.

>   * 母： 妹【いもうと】の誕生日だよ。ケーキでも買ったら？ → Mother: It's your little sister's
> birthday. How about buying her a cake or something?
>

But if you're just asking for the listener's opinion on something, like your
example "What do you think about this sweater?", `～（について）どう思う？`

>   * このセーター（について）、どう（思う）？
>

