About donde and dónde
La cama era muy grande. No sabía dónde ponerla. Shouldn't it be donde instead of dónde here? Thanks.
2 Answers
When donde is used as for things like a relative pronoun it doesn't have the accent.
I went to the store where the shoes were on sale. (donde)
In interrogatives and exclamations the dónde has the accent mark.
It, likewise, is an interrogative pronoun in indirect questions like yours. (dónde)
Where don't I know that I put it?
The same thing happens with other relative/interrogative pronoun like cómo/como and qué/que.
No sé qué voy a hacer.
What don't I know to do?
No sé cómo hacerlo.
How don't I know to do it?
With como and que it's a little easier to spot. If How, rather than like or as seems to fit it, cómo usually takes an accent. If What rather than ****that, who, which**** fits the qué usually takes an accent. With donde you don't get those hints. It's Where in both cases. Neither do you get hints with quién/quien or cuál/cual.
You just have to learn to decide if it's being used as an interrogative pronoun or a relative pronoun.
Pay special attention to the last sentence in this article. It's why I was using terms like usually.
HI zhou, this is an indirect question, so it needs to have an accent. Look at Quentin's answer, he knows everything. 
