close 和closely 用作副词意义上有差别。

Close 是指距离、场所、地点等的“接近，靠近”，可以说是一种实际意义上的“接近”。Close to有“接近，几乎，大概，差不多”的意思。例如：

We live close to the church.

我们住在教堂附近。

They sat close together.

他们紧挨着坐在一起。

He came close to losing his temper.

他差一点发脾气了。

close当形容词则为“亲近、亲密”的意思

例如：Tom and I were really close when we were in high school.

Closely 是指抽象意义上的“接近”，多用比喻意义，有“亲密地，严密地，仔细地”等意思。例如：

The secret must be closely guarded.

这个秘密要严加保守。

He is looking at the bill closely.

他正仔细地看着帐单。

closely

主要是副词功能,用来修饰动词时表达“很接近地、紧密地、密切地”

例如：The crowd closely watch the players' every move as the clock winds down.随着时间的推移，观众们密切注视着运动员们的一举一动。

副词close 通常放在动词之后，但在过去分词之前要用 closely。如：

He was standing close to the door. 他靠门站着。

We followed close(ly) behind him. 我们紧跟在他后面。

We were so closely packed in the elevator that I could hardly move. 我们在电梯里紧紧地挤在一起，我几乎不能动弹。

She listened closely while he read. 他读时她仔细听着。

He closely studied this problem. 他仔细研究过这个问题。

The two events are closely connected. 这两件事有着紧密的联系。

[拓展] 由close 和closely这种意义上的区别，我们可以很轻松地区别high和highly、wide和widely、deep和deeply等一类词。带-ly的副词往往用作抽象意义或比喻意义，而不带-ly的副词多用作实际意义。例如：

He threw the ball high into the air.

他把球高高地抛向空中。（high 是指实际意义上的“高”）

They spoke highly of his behaviour.

他们高度地赞扬了他的行为。（highly 用作比喻意义“高度地”）

The dentist asked me to open wide.

牙医要我张大嘴巴。（wide 是指实际意义的“大、阔”）

He is widely read.

他博览群书。（widely 是指抽象意义上的“广泛地”）