Correct

暂时 vs 一时

/ zànshí vs yīshí /
Strokes

Formula

1
是 + 暂时 + 的
2
一时……一时……

Definition

暂时 as an Adjective, and 一时 as an Adjective or Noun, which means [for the time being; for a short while; momentary; moment].

Example

暂时 as Adjective indicates within a short time. It can function as attributive or adverbial. It cannot function as the predicate of a sentence unless it is used in the phrase 是暂时的 (temporary).
In example ①, 暂时 can be replaced by 一时 (the detailed explanation will come next), because it is followed by a negative phrase (the detailed explanation will come next), In all the other examples, 暂时 cannot be so replaced.
是 + 暂时 + 的
1
Zhège
这个
xīn
cuòshī
措施
zànshí
暂时
  
(
shí
  
)
hái
néng
shíxíng
实行
  

The new measure cannot be carried out at present.

2
yòng
服用
zhèzhǒng
这种
yào
hòu
yǒuxiē
有些
kǒu
口渴
  
,
zhè
shì
zànshí
暂时
de
xiànxiàng
现象
  
,
hěnkuài
很快
jiù
huì
xiāoshī
消失
  

You will feel a litle thisty after taking the medicine;tha side efect is temporary and will disappear soon.

3
Yīn
xiàn
线路
shēng
发生
zhàng
故障
  
,
zhège
这个
ōu
地区
zànshí
暂时
tíngdiàn
停电
  

There is temporary power failue here for ther's somehing wrong with the electrcity circuit.

4
men
他们
zànshí
暂时
zài
zhè
这里
zhù
tiān
  
,
hěnkuài
很快
jiù
bānzǒu
搬走
  

They stayed here temporarly, and they would move very soon.

5
Zhè
gōngzuò
工作
shì
zànshí
暂时
de
  
,
gàn
wán
jiù
zǒu
  

This isatemporary job, and I will leave here as soon as I finish it.

一时 as an Adjective also indicate within a short time but seems longer than the time indicated by 暂时. It is mostly used in a negative sentence or a sentence with a negative sense and functions as an adverbial.
6
Zhème
这么
hòu
de
běn
shū
  
,
shí
  
(
zànshí
暂时
  
)
kàn
wán
  
,
xiàxīng
下星期
zài
hái
  

I canot finish such a thick book at a lime, so I will returm it to you next week.

7
Zhè
这里
shí
  
(
zànshí
暂时
  
)
ānpái
安排
le
zhème
这么
duō
rén
de
gōngzuò
工作
  

There are no enough vacancies for so many people at a time.

8
Zhème
这么
复杂
de
wèn
问题
  
,
shí
hěn
nán
huí
回答
chūlái
出来
  

It's too diffcult for me to answer the question for the moment.

9
Zuòshì
做事
yào
zháshishí
扎扎实实
  
,
néng
zhī
píng
shí
de
qíng
热情
  

You should work steadily and cannot rely on an instant's enthusiasm.

一时 indicates (some situations, phenomenon, etc. occur) irregularly, only accidentally, functioning as an adverbial; whle 暂时 cannot be used like this.
10
shí
gāoxìng
高兴
  
,
gěi
jiā
大家
chàng
le
duàn
jīng
京剧
  

He sang us an act of Peking Opera at a temporary pleasure.

11
shí
lái
le
xìngzhì
兴致
  
,
yāo
ge
péngyou
朋友
shān
爬山
le
  

He invited a few friends to go climbing on impulse.

一时 as a Noun indicates a short time.
12
Jīntiān
今天
zhíbān
值班
  
,
shí
gǎn
kāi
离开
  

I'm on duty today, and I cannot leave the work for a short while.

13
Xiūxi
休息
xià
  
,
yònggōng
用功
zài
zhè
shí
  

Take a break, and I think diligence does not necessarily mean this moment.

14
kàn
shí
bànhuìr  
半会儿
shì
huì
不会
答复
men
我们
de
  

I think he will make no reply to us in a little while.

一时 as a Noun indicates a period of time.
15
Zhèzhǒng
这种
yàngshì
样式
de
gāogēnxié
高跟鞋
céngjīng
曾经
fēngxíngshí
风行一时
  

The high-heeled shoes of this style were once in fashion.

16
此一
shí
  
,
shí
  
,
zhè
这次
de
shìqing
事情
zěnme
怎么
néng
gēn
shàng
上次
xiāng
相比
ne
  
?

How can you compare it with last one? For time is different.

一时……一时…… indicates that different actions or situations take place alternatively in a short time; while 暂时 has no such usage.
一时……一时……
17
Bìngrén
病人
de
bìngqíng
病情
wěndìng
稳定
  
,
shí
hǎo
  
,
shí
huài
  

The patient's symptom is unstable, for it is now better and now worse.

18
shí
shí
xiào
  
,
dào
到底
zěnme
怎么
huí
shì
  
?

What's wrong with her? Now cry, now laugh.

19
shí
zhèyàng
这样
shuō
  
,
shí
yàng
那样
shuō
  
,
ge
哪个
shì
zhēn
de
  
?

Which is correct? For you told us about it differenly at different time.