This is a weakness in human thinking, but one which we have a need to overcome. YES -- we almost always initially understand concepts with physical examples, which we then try to generalize.
The essence of having a philosophic mindset, is to try to identify the hidden walls of the boxes that we think within, explore those walls, and then deliberately decide whether to continue to work with those walls or not. Learning to think about abstractions without having physical examples is a skill that philosophers (and theoretical physicists) need to cultivate.
A suggested starting point -- take a page of a dictionary, and think about the ideas presented there. Here is an example: http://i0.wp.com/olddesignshop.com/wp-content/uploads/2014/12/OldDesignShop_DictionaryPageParty.jpg
Partake is not an object, it is a social activity which is generalized. You can't point to a pencil or other inert object. Thinking thru "partake" will help a lot.
Partial, as defined here, is solely an attitudinal description, and the attitude may not even be conscious. That will help a lot to consider as well.
Participate is another generalized social concept, and another interesting part of its generalization is that one starts thinking in terms of humans in a social situation, but "participant" can be analogously applied to all sort of other things. A log in my fireplace is a participant in creating a fire. A locking bar for a sliding glass door is a participant in securing my home from unwelcome entry.
Participle -- you will not find ANY physical examples for this abstract concept. Examples solely exist in the abstract realm of language rules.
Train your mind to think about abstractions.