糖类、油脂和蛋白质的共同特点是A.均是高分子化合物 B.常温下,遇碘水均会显蓝色C.均只含有C、H、O三种元素 D.均是生命活动必不可少的物质
I can’t leave. She told me that I ______ stay here until she comes back.
—— Do you mind my opening the window? It’s a bit hot in here. —— ______ , as a matter of fact
It’s high time you had your hair cut ; it’s getting _______ .
My friend showed me round the town, ______ was very kind of him.
They use computers to keep the traffic _______ smoothly.