1. What about dinner at my place?
2. What about dinner in my place?
3. What about dinner at my house?
4. What about dinner at my apartment?
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Are they all correct? Do we have to use 'at' or'in'? Are both OK? What is the difference between 'at' and 'in'?
I wouldn't use "in" but I think any of the others are fine.
Anonymous is right. 1, 3, and 4 are right. 2 is not.
All of the sentences you mentioned are grammatically correct, but there are slight differences in meaning.
1. "What about dinner at my place?" - This implies that the dinner will take place at a location that is considered your home or personal space. "At" is used to indicate a specific location.
2. "What about dinner in my place?" - This could be interpreted as having dinner inside a specific room or area within your place. The use of "in" suggests a more confined or enclosed space.
3. "What about dinner at my house?" - Similar to the first sentence, this implies having dinner at a particular location, which is your house.
4. "What about dinner at my apartment?" - This is the same as the first sentence, but specifically mentions that the location is an apartment.
The choice between "at" and "in" depends on the context and the specific location being referred to. Generally, "at" is used to indicate a general location or address, while "in" suggests being inside a specific space within that location.
For example, if you invite someone to dinner at your place (sentence 1), it means they would come to your home and have dinner there. However, if you say dinner in your bedroom, it suggests having dinner specifically within your bedroom.
Both "at" and "in" can be used to convey the idea of location, but the choice depends on the specific context and the level of detail you want to convey.