List out the ideas discussed in the following sentence and then classify the ideas as one of the four classes whose definition is given as per instructions.
Instruction for classifying:
The ideas shall be a word or continuous set of words occurring only in the sentence.
All words shall be classified to one class.
A word in the sentence shall not be present as part of more than one class.
Class 1 - object: ideas that can be attributed to a physical form.
Class 2 - concepts: ideas that are abstract and cannot be attributed a physical form.
Class 3 - activity: ideas that involves an activity or process.
Class 4 - event: ideas that corresponds to an event.
identify the subject of the sentence.
Sentence: "Physical stores allow to receive assistance with customer’s purchase."
Generate output in row wise format with two columns: ideas - class. Append subject of the sentence as the last row.
 Respond with at most 300 words.
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