hardly, barely, scarcely
这组词意思相近，它们的区别是：
hardly常用来修饰表示能力的词; scarcely强调不足,常与enough, sufficient等词连用; barely强调“勉强”。例如:
The enemy are so exhausted that they are hardly able to fight any longer.敌人已经疲惫得简直不能再战了。
The field is so thickly grown with rice that there is scarcely sufficient room for one to work in.稻子长得很密,人们简直无法下田劳动了。
I have barely enough money to buy a cup of coffee.我的钱刚好够买一杯咖啡。
hardly, hard
1.hard可作形容词或副词; 而hardly只能用作副词。
2.hard意指“坚硬”“痛苦的”“结实的”“艰难地”“困苦地”“费力地”“困难地”; 而hardly是“几乎不”“几乎没有”的意思。
hardly...when, as soon as, no sooner...than
这三个短语都可表示“一…就…”。它们的区别是：
1.as soon as可转化为no sooner...than或hardly...when结构。例如:
As soon as I heard the knock I opened the door.
No sooner had I heard the knock than I opened the door.
Hardly had I heard the knock when I opened the door.
当我听到敲门声,我马上就开门了。
2.as soon as通常用于一般时态, no hardly...than和hardly...when通常用于过去完成时。例如:
As soon as you finish your job, let me know.你一完成工作就告诉我一声。
No sooner had the doctor arrived than he began treating the sick.医生一到马上就抢救病人。
I had hardly started when it began to rain.我刚动身就下起雨来了。
hardly，scarcely
这一对副词都有“几乎不”、“几乎没有”的否定意味，但涵义重心有细微的差异。
hardly强调“困难”，指程度而言，常用以修饰表示能力的词，与can、ever、any等词连用。
scarcely强调“不足”，主要指数量而言，常与enough、sufficient、any或数词连用。
