I know the phrase "一下儿" can be appended to a verb to indicate the action takes short time or less effort, for example "看一下儿". However, some verbs cannot be appended by "一下儿", since the sentence won't make sense, such as "我去学校踢一下儿足球". So my question is: what types of verbs cannot be appended by "一下儿"? Is there a rule for it?
To give you more examples, it is correct to say 我借一下儿你的会员卡, but it is wrong to say 我还一下儿你的会员卡. Why?
In English it's correct to say "I'll borrow your membership card for a little while", but wrong to say "I'll return your membership card for a little while". Why? Since the membership card belongs to you, the action of returning results in something long-term or permanent, and "returning for a little while" makes no sense. The same is true for the two sentences in Chinese. The reason why "一下儿" can be appended to one verb and not the other isn't about grammar, but semantics.
一下儿 here indicates a brief period or relaxed and casual manner of an action.
我去学校踢一下儿足球 -> For a while 我借一下儿你的会员 -> For a while 我想亲你一下 -> Relaxed and casual manner
As to "我还一下儿你的会员卡", it sounds weird because it can neither fall into "for a while" nor "relaxed and casual manner"
I'm Cindy Li, a native Chinese teacher from iChineseLearning. Hope my answer will help you! 一下 after a verb can have a number of uses, but let me try explaining the simplest and most obvious use for you.
You can translate 一下 as "a bit/ a short while". It's often added to the verb to make the verb sound less serious, less formal (and if use appropriately, you'll sound more polite).
First take some examples in English: Compare "I'll read" with "I'll have a read", "Taste it!" with "Have a taste!" you'll see that by adding "have a", the language sound less serious, less formal. Similarly, if you add 一下 to the verb 说 (say) or to 休息, you'll have the following: 说= say/ speak vs 说一下 = have a word (about something). 休息= rest vs 休息一下 = have a rest. So the ones with 一下 sound a bit less stiff, less formal.
I hope the above has given you some idea, but ask again if you're still not quite sure.
一下儿 could be used for a short time or a less important matter.
你到我们家来一下儿好吗?
Could you please come over my home?
我今天不舒服, 你和老师说一下儿好吗？
Could you please tell our teacher that I do not feel very well?
In English, it is not necessary to translate it word by word.
In fact, the sentence "我去学习踢一下儿足球。" is right. I often use this expression and I am a Chinese. The phrase "一下儿" is equivalent to "for a while".
I think "一下" mostly emphasize "I'll be back soon"or"I'll not let you wait for a long time",it's necessary to use "一下" when you borrow something or you can say"能把你的……借给我吗". And other times it's same as "一会儿". You shouldn't say"还一下",just like you shouldn't say "I'm giving your book back to you". I think someone use like "我去学校踢一下儿足球。" is just some people's hobby and it means nothing....I just say"我去学校踢足球了". When you use here "一下“ it sounds like you just want to have a try. PS:Maybe people live in beijing add"儿",but I usually say “一下”
In most cases,it's like "一会儿" in Chinese.They both mean that you are going to do something for a short while or are used to make the conversation sounds natural,don't really mean anything.
I'd say all the usage of "一下(儿)" in the examples given in the question are legit. My dictionary (Modern Chinese Dictionary came with Mac OS X) doesn't say any there is any special cases for the usage of 一下 after a verb. And my personal experience as a native speaker suggests the same.
First let me try to further explain the usage of "一下(儿)".
One can understand 下 as a standard quantifier or measure word for actions. In Chinese high school, English teachers would often teach the student the difference between instant verbs and continuous verbs. I'm not sure whether these concepts are legit in English grammar of not, but I'll borrow the two here. Normally for instant verbs such as to kiss(亲) or to kick(踢), 一下 could be easily understand as one execution or instance of the corresponding action. For other verbs such as to eat(吃) or to run(跑), it might be hard to determine the extend of the action. But when one see such action as an activity, then they can be quantified. For example eat as an activity could be from the start to the finish of a meal.
In Chinese, quantifiers are commonly used in an ambiguous manner to increase their flexibility. In the same way 一下 turned to a figurative expression of the carry out of an action or activity casually, or with mild effort or interest, for a little while, or just do something a little bit, and some times just to make the voice more informal or approachable. Basically it's express the less in some characters of the instance of the action or activity, be it time or effort or other possible aspects.
And as a native speaker, I couldn't think of any situation that is to wrong to add 一下 after a verb.
Now let's look at the two examples in the questions that are doubtful.
我去学校踢一下儿足球。
I will go/went to the school to play some/a little football.
Here 踢足球 is obviously the activity of playing football not the action of kicking the ball. So it could be treated as the same way as a instant verb. Thus the usage are acceptable and legit.
我还一下儿你的会员卡。
I return your membership card.
The usage of 一下 is also legit here but the sentence does sound awkward. The reason for that is although it is a grammatically correct sentence, it doesn't make much sense. The problem here is that it's a declarative statement without any indication of grammar aspect or tense. If you rip 一下 out of this sentence, it would become the sentence below and still feels weird.
我还你的会员卡。
Now, remember this is a sentence not a modified noun phrase. The intention of this sentence is hard to deduce without context. It would be something like "I return your membership card". So you can see even in English it sounds a bit weird. Normally it should be something like：
我来还(一下)你的会员卡。
I came to return your member ship card.
So the point is that it's correct but because there isn't a common situation to use such construction in real life, it sounds weird and this has nothing to do with the usage of 一下. It's definitely a correct sentence in theory and in certain contexts.
