deep/deeply
Deep作副词用时，强调的是时间和空间上的由上到下由外到内距离大，是可以感知的，有形的。如：
The miners were trapped deep underground.矿工被困在地下深处。
They talked deep into the night.他们谈到了深夜。
Deeply相当于very much，“非常”。如：
They were deeply disturbed by the accident.那场事故使他们深感不安。
They were deeply in love.他们深坠爱河。
可见，deeply是无形的、抽象的；deep是具体的、可感知的。Deep也可以抽象地使用，但要与down连用，表示人的本性、心地。如：
She can seem stern, but deep down she’s a very kind person. 她看上去可能很严厉，其实心地非常善良。