However, black holes can be detectable if they interact with matter, e. g. by sucking in gas from an orbiting star.
然而，黑洞可以是可发现的，如果他们与问题互动，即通过吮在气体从一个轨道的星。
2
A few years ago, a resignation letter from a rising star in the company prompted CEO G. Brint Ryan to reevaluate the firm's focus on long hours and face time.