Tom here for BBC Learning English.

我是 BBC 英語學習頻道的 Tom。

Today, I'm going to explain the difference between what and which in questions.

今天，我要來解釋「what」和「which」在問句中的差別。

'What' is used to ask a question which has a lot of possible answers.

我們會用「what」來問有好幾種可能的答案的問題。

Consider the question:

想想看這個問題：

What do you want to eat for lunch?

你午餐想吃什麼？

Here, there are no choices to limit your reply.

你的答案沒有選項限制。

You could choose anything you want.

你可以選任何你想要吃的東西。

We use 'which' when we have options to choose from.

當我們有選項時，我們用「which」。

So, here we have two choices – a sandwich and a melon.

所以呢，我們現在有兩個選項，三明治和西瓜。

So I can say: Which do you want to eat?

所以我可以說：你想吃哪一個？

The sandwich or the melon?

三明治還是西瓜？

Now, next time you need to ask a question, you'll know which word to use.

下次你需要問問題時，你就知道該用哪個詞了。

'What' for anything and 'which' when you have a choice.

任意事物用「what」，有選項時用「which」。