🧩 词语组成解析
seven
['sɛvn]
num. 七;七个;第七;
n. 七;七个;
🗣️ 情景例句
Yes, I'm ready.
是的，我想好了。
That was a close call.
太危险了。
So the number of stars that we know exist is now estimated at about 300 million million million.
因此，我们所知道的现有恒星数目估计约有30亿×1000亿颗。