v.知道( know的过去式 );了解;
例句:
He knew they were tracing him.
他知道他们正在追踪他.
Three months have passed before we knew it.
不知不觉已过了三个月.
When his wish was realized, his joy knew no measure.
当他的愿望实现时, 他不知道有多高兴.