It was not until 1911, _______ the first vitamin was identified, _______ people realized the importance of it．

172. — Where did you see him— It was in the hotel ______.

My parents _____in Hong KongThey were born there and have lived nowhere else[ ]

I don’t know ________ the future holds in store for me, but I’ll face the storms of life bravely

You____think you are clever, but that doesn’t give you the right to order me about.