It's not designed for anyone under age eighteen.
它不是为18岁以下者设计的。
He was employed by them for eighteen years.
他为他们工作了18年。
Their two faces were hardly more than eighteen inches apart.
他俩的'脸相隔还不到18英寸。
Eighteen boats plied the 1,000 miles of river along a trading route
18艘船沿着贸易航线往返于1,000英里的河面上。
He was a kid really, not more than eighteen or nineteen.
他实际上还是个孩子，最多不过十八九岁。