Oxford Advanced Learner's Dictionary gives the definition of sink as follows:
a large open container [...] that you use for washing dishes in
My question is whether the preposition 'in' is necessary.
What about the following? Are the prepositions necessary?
I bought a pair of chopsticks for eating rice with.
I bought a pair of chopsticks to eat rice with.
I bought a house to live in.
Firstly, you have to realize that the purpose of a dictionary is to describe the word in such a way that people can understand the object associated with the word. A "sink" must contain the objects being washed or it wouldn't be a sink. The inclusion of "in" is helpful in conveying this and removing it would impact the effectiveness of the definition:
1) a large open container [...] that you use for washing dishes in
2) a large open container [...] that you use for washing dishes
The "large open" modifier implies that you put the dishes into the sink but including "in" makes it much more explicit. Otherwise, you could have a large open container that washes dishes akin to a washboard. While it wouldn't make a whole lot of sense, the dictionary is specifically trying to associate the preposition "in" with "sink" because that is how you use a sink: You put dishes in the sink in order to wash them.
For common, everyday usage you could remove "in" and no one would be confused but this pattern is common in dictionary entries.
"I bought a pair of chopsticks to eat rice" could be misinterpreted to mean that your chopsticks are the things eating rice. "I bought a house to live" could be misinterpreted to mean that without a house, you would die. Similarly, the sink is not washing your dishes.
I think it depends on your sentence structure and not the -ing form of the verb. You actually did not use the verb+ing construction in all your sentences.
Because of your use of to in your sentence, I think the preposition is necessary depending on the verb, even though the sentence can be understood if the preposition was left off.
You don't buy a house to live. You buy it to live in.
You don't but a chair to sit. You buy it to sit (up)on.
But, A car allows you to travel. You can buy a plane to fly.
It appears that the construction you question is not a fixed one.
Here are three other definitions of sink (verb):
- To cause to descend beneath a surface: sink a ship.
- To cause to drop or lower: sank the bucket into the well.
- To force into the ground: sink a piling.
to drop needs no further preposition, nor does into
Of chopsticks
either one of a pair of thin sticks that are used especially by people in Asia to pick up and eat food. There is no with in this definition.
Holy cow... People put a lot of nonsense down for such simple questions.
First, prepositions can act as adverbs, and prepositional phrases can act as adjectives and adverbs. As with any other adjective or adverb, you can remove them if they are not essential for understanding.
Example:
"I am going to go wash my red corvette." 'Red' is an adjective and not essential.
"I am going to go wash my corvette."
If I said, "I am going to go wash my red corvette with soap and water." My prepositional phrase "with soap and water" is acting adverbially to modify the verb "wash"; it is also non-essential and I can get rid of it.
In your first example:
"I bought chopsticks for eating rice with." "for eating rice" is a prepositional phrase acting adjectivally to describe "chopsticks". Most all of us know what chopsticks are for, which is why native speakers are telling you to get rid of it. They know it "sounds bad", but no one seems willing to tell you why it sounds bad (not accurately, at least).
"with" is no longer acting as a preposition, but as an adverb to modify the verb "eating". It is non-essential and can be removed.
The next example, "I bought a pair of chopsticks to eat rice with." is NOT using a prepositional phrase as the modifier; "to eat rice with" is an infinitive phrase.
An infinitive phrase can act as a noun, an adjective, or an adverb.
That means an infinitive can be removed when it is an adjective or adverb, but not when it is a noun since it will be performing an essential function.
For example, in "I love to eat." 'to eat' is an infinitive forming the direct object of the transitive verb "love". If we take it out, we will deprive our sentence of meaning... "I love..."
The reason this infinitive "sound better" to all these native speakers is because it is not describing the chopsticks, it is acting adverbially to say why you bought the chopsticks. This is not essential to the meaning unless you need the reader to understand that the chopsticks are for rice and not noodles. If that is essential to the understanding your purchase, you would need it:
"My old chopsticks are for eating noodles."
"I bought these chopsticks to eat rice with."
If you just said "I bought these chopsticks.", it would deprive the sentence of its essential meaning.
Same application to your last sentence:
"I bought a house to live in." uses an infinitive phrase "to live in" adverbially to establish why you bought a house, or it could be used adjectivally to describe the house, depending on context. You only need to keep this infinitive if it is essential to meaning.
"George bought a house on this street to lease out, but 'I bought a house [to live in]." "to live in" is essential to meaning and cannot be omitted.
"in" is no longer acting as a preposition, but as an adverb to describe where you "lived"--You live in the house, not on the house.
