根据现行有关规定，关于ETF交易，下列说法正确的有( )。

A．投资者可以通过申购赎回或买卖交易两种方式参与ETF的投资

B．投资者需用组合证券进行申购、赎回ETF份额

C．投资者的申购、赎回ETF份额的申报指令可以撤销

D．当日申购的基金份额，同日可以卖出和赎回

根据句意及首字母提示补全单词。

1.—What can we do to help Mingming? He's too poor to go to school next year.

   —Why not r______some money for him?

2. —Wow, you have such a good collection of coins!

    —I love collecting coins, but now I feel worried for I can't find enough room to s_____ them.

3. —Are you i______ in skating?

    —Sure. I am a skating lover.

4. —When did you get your first p_____of skates?

    —At che age of six,when I began to learn skating.

5.—Do you know what the longest distance run is?

  —Of course it is m______