下列时间状语均表示“从过去开始并一直延续到现在” （记住这些时间状语）。
（1）since +时间点
a. I’ve worked in this company since 2016.
b. I’ve worked in this company since I left school. （从句用一般过去时）
（2）for +时间段
a. I’ve worked in this company for three years.
b. Great changes have taken place in Beijing for the past few years.
近几年，北京发生了很大的变化。
（3）表示“到目前为止……”
until now　up until now　up to now　up till now　so far
例句
We have up until now failed to take any action to decide on a common language that would further communication between nations.
到目前为止，我们尚未采取任何行动来确定一门国际通用语言，以促进国家间的交流。
（4）表示“最近几世纪/年/月以来……”
for the past few years
over the past few years
during the last three months
for the last few centuries
through centuries
throughout history
例句
a. Throughout history man has had to accept the fact that all living things must die, for the very nature of life includes death.
自古以来，人类就必须接受这样的事实：一切生命体最终都会消亡，因为生命的本质包含了死亡。
b. Through centuries the bizarre antics of sleepwalkers have puzzled police, perplexed scientists and fascinated writers.
几个世纪以来，梦游者古怪的行为让警察和科学家大为困惑，同时也让很多作家为之着迷。