It's getting late. Please excuse me, but I must leave right away.
时间不早了。对不起,我得赶紧走了。
An old dog cannot alter its way of barking.
老狗难改吠声。
Who could have imagined, in the mid 1970s, for example, that by the end of the 20th century, computers would be as common in people's homes as TV sets?