In a language exercise, I was supposed to write the following in Japanese: "Please close the window." Intuitively, I thought, since 窓 is the direct object of 閉めて, then probably
窓を閉めてください
I found out the correct answer is:
窓は閉めてください。
My question is, is 窓を閉めてください a grammatical sentence at all? If it is, then does it mean something different from 窓は閉めてください?
Further on in the same exercise, I came across another sentence:
その窓を閉めてください
I thought, strange, why is it now を and not は? So now my other question is: is その窓は閉めてください grammatical? And if it is, does it mean something different from その窓を閉めてください?
May I add that it's an online exercise, so I had no teacher to ask. Thanks for helping.