首的用法和样例：
例句
-
首先，要向杯子里放一小片锌板。
You should first put a small piece of zinc plate into the cup. -
首先，画一条水平线。
First, draw a horizontal line. -
工业革命首先在英国发生。
The industrial revolution had taken place in England first. -
那首领拿一些玻璃块替换了那些钻石。
The chief interchanged the diamond with some pieces of glass. -
美国总统是行政首脑。
The President of the United States is the chief executive. -
国家元首被军队废黜了。
The head of state was deposed by the army.
