1.the national debt was made into a secure investment, no longer liable to repudiation at the caprice of the monarch.
国债成了牢固的投资，不再会有君主一时性起拒绝兑付的危险。
2.ABS are one of the most secure investment vehicles from a credit standpoint.
从信用角度看，资产支持型证券是最安全的投资工具之一。
3.Land in a growing city is a secure investment.
在一个逐渐扩大的都市里，地产是一种安全的投资。
4.Estate in this city is a secure investment.
在这座城市，地产是可靠的投资。
5.A lot of inn-keeper secure investment now very big, but limit cost is very low;
现在很多店家固定投入很大，但边际成本很低；